Class Query
This class represents a Relational database SQL Query. A query can be of different types like select, update, insert and delete. Exposes the methods for dynamically constructing each query part, execute it and transform it to a specific SQL dialect.
Property Summary
-
$_connection protected
Cake\Datasource\ConnectionInterface
Connection instance to be used to execute this query.
-
$_dirty protected
bool
Indicates whether internal state of this query was changed, this is used to discard internal cached objects such as the transformed query or the reference to the executed statement.
-
$_functionsBuilder protected
FunctionsBuilder
Instance of functions builder object used for generating arbitrary SQL functions.
-
$_iterator protected
Cake\Database\StatementInterface
Statement object resulting from executing this query.
-
$_parts protected
array
List of SQL parts that will be used to build this query.
-
$_resultDecorators protected
array
A list of callback functions to be called to alter each row from resulting statement upon retrieval. Each one of the callback function will receive the row array as first argument.
-
$_type protected
string
Type of this query (select, insert, update, delete).
-
$_typeMap protected
Cake\Database\TypeMap
-
$_useBufferedResults protected
bool
Boolean for tracking whether or not buffered results are enabled.
-
$_valueBinder protected
ValueBinder
The object responsible for generating query placeholders and temporarily store values associated to each of those.
Method Summary
-
__clone() public
Do a deep clone on this object.
-
__construct() public
Constructor.
-
__debugInfo() public
Returns an array that can be used to describe the internal state of this object.
-
__toString() public
Returns string representation of this query (complete SQL statement).
-
_conjugate() protected
Helper function used to build conditions by composing QueryExpression objects.
-
_decorateStatement() protected
Auxiliary function used to wrap the original statement from the driver with any registered callbacks.
-
_dirty() protected
Marks a query as dirty, removing any preprocessed information from in memory caching.
-
_makeJoin() protected
Returns an array that can be passed to the join method describing a single join clause
-
andHaving() public
Connects any previously defined set of conditions to the provided list using the AND operator in the HAVING clause. This method operates in exactly the same way as the method
andWhere()
does. Please refer to its documentation for an insight on how to using each parameter. -
andWhere() public
Connects any previously defined set of conditions to the provided list using the AND operator. This function accepts the conditions list in the same format as the method
where
does, hence you can use arrays, expression objects callback functions or strings. -
bind() public
Associates a query placeholder to a value and a type.
-
bufferResults() public
Enable/Disable buffered results.
-
clause() public
Returns any data that was stored in the specified clause. This is useful for modifying any internal part of the query and it is used by the SQL dialects to transform the query accordingly before it is executed. The valid clauses that can be retrieved are: delete, update, set, insert, values, select, distinct, from, join, set, where, group, having, order, limit, offset and union.
-
connection() public
Sets the connection instance to be used for executing and transforming this query When called with a null argument, it will return the current connection instance.
-
decorateResults() public
Registers a callback to be executed for each result that is fetched from the result set, the callback function will receive as first parameter an array with the raw data from the database for every row that is fetched and must return the row with any possible modifications.
-
defaultTypes() public
Allows setting default types when chaining query
-
delete() public
Create a delete query.
-
distinct() public
Adds a DISTINCT clause to the query to remove duplicates from the result set. This clause can only be used for select statements.
-
epilog() public
A string or expression that will be appended to the generated query
-
execute() public
Compiles the SQL representation of this query and executes it using the configured connection object. Returns the resulting statement object.
-
from() public
Adds a single or multiple tables to be used in the FROM clause for this query. Tables can be passed as an array of strings, array of expression objects, a single expression or a single string.
-
func() public
Returns an instance of a functions builder object that can be used for generating arbitrary SQL functions.
-
getIterator() public
Executes this query and returns a results iterator. This function is required for implementing the IteratorAggregate interface and allows the query to be iterated without having to call execute() manually, thus making it look like a result set instead of the query itself.
-
group() public
Adds a single or multiple fields to be used in the GROUP BY clause for this query. Fields can be passed as an array of strings, array of expression objects, a single expression or a single string.
-
having() public
Adds a condition or set of conditions to be used in the HAVING clause for this query. This method operates in exactly the same way as the method
where()
does. Please refer to its documentation for an insight on how to using each parameter. -
innerJoin() public
Adds a single INNER JOIN clause to the query.
-
insert() public
Create an insert query.
-
into() public
Set the table name for insert queries.
-
join() public
Adds a single or multiple tables to be used as JOIN clauses to this query. Tables can be passed as an array of strings, an array describing the join parts, an array with multiple join descriptions, or a single string.
-
leftJoin() public
Adds a single LEFT JOIN clause to the query.
-
limit() public
Sets the number of records that should be retrieved from database, accepts an integer or an expression object that evaluates to an integer. In some databases, this operation might not be supported or will require the query to be transformed in order to limit the result set size.
-
modifier() public
Adds a single or multiple SELECT modifiers to be used in the SELECT.
-
newExpr() public
Returns a new QueryExpression object. This is a handy function when building complex queries using a fluent interface. You can also override this function in subclasses to use a more specialized QueryExpression class if required.
-
offset() public
Sets the number of records that should be skipped from the original result set This is commonly used for paginating large results. Accepts an integer or an expression object that evaluates to an integer.
-
orHaving() public
Connects any previously defined set of conditions to the provided list using the OR operator in the HAVING clause. This method operates in exactly the same way as the method
orWhere()
does. Please refer to its documentation for an insight on how to using each parameter. -
orWhere() public
Connects any previously defined set of conditions to the provided list using the OR operator. This function accepts the conditions list in the same format as the method
where
does, hence you can use arrays, expression objects callback functions or strings. -
order() public
Adds a single or multiple fields to be used in the ORDER clause for this query. Fields can be passed as an array of strings, array of expression objects, a single expression or a single string.
-
orderAsc() public
Add an ORDER BY clause with an ASC direction.
-
orderDesc() public
Add an ORDER BY clause with an ASC direction.
-
page() public
Set the page of results you want.
-
removeJoin() public
Remove a join if it has been defined.
-
rightJoin() public
Adds a single RIGHT JOIN clause to the query.
-
select() public
Adds new fields to be returned by a SELECT statement when this query is executed. Fields can be passed as an array of strings, array of expression objects, a single expression or a single string.
-
set() public
Set one or many fields to update.
-
sql() public
Returns the SQL representation of this object.
-
traverse() public
Will iterate over every specified part. Traversing functions can aggregate results using variables in the closure or instance variables. This function is commonly used as a way for traversing all query parts that are going to be used for constructing a query.
-
traverseExpressions() public
This function works similar to the traverse() function, with the difference that it does a full depth traversal of the entire expression tree. This will execute the provided callback function for each ExpressionInterface object that is stored inside this query at any nesting depth in any part of the query.
-
type() public
Returns the type of this query (select, insert, update, delete)
-
typeMap() public
Creates a new TypeMap if $typeMap is an array, otherwise returns the existing type map or exchanges it for the given one.
-
union() public
Adds a complete query to be used in conjunction with an UNION operator with this query. This is used to combine the result set of this query with the one that will be returned by the passed query. You can add as many queries as you required by calling multiple times this method with different queries.
-
unionAll() public
Adds a complete query to be used in conjunction with the UNION ALL operator with this query. This is used to combine the result set of this query with the one that will be returned by the passed query. You can add as many queries as you required by calling multiple times this method with different queries.
-
update() public
Create an update query.
-
valueBinder() public
Returns the currently used ValueBinder instance. If a value is passed, it will be set as the new instance to be used.
-
values() public
Set the values for an insert query.
-
where() public
Adds a condition or set of conditions to be used in the WHERE clause for this query. Conditions can be expressed as an array of fields as keys with comparison operators in it, the values for the array will be used for comparing the field to such literal. Finally, conditions can be expressed as a single string or an array of strings.
Method Detail
__clone() ¶ public
__clone(): void
Do a deep clone on this object.
Will clone all of the expression objects used in each of the clauses, as well as the valueBinder.
Returns
void
__construct() ¶ public
__construct(Cake\Datasource\ConnectionInterface $connection)
Constructor.
Parameters
-
Cake\Datasource\ConnectionInterface
$connection The connection object to be used for transforming and executing this query
__debugInfo() ¶ public
__debugInfo(): array
Returns an array that can be used to describe the internal state of this object.
Returns
array
__toString() ¶ public
__toString(): string
Returns string representation of this query (complete SQL statement).
Returns
string
_conjugate() ¶ protected
_conjugate(string $part, string|null|array|ExpressionInterface|callback $append, string $conjunction, array $types): void
Helper function used to build conditions by composing QueryExpression objects.
Parameters
-
string
$part Name of the query part to append the new part to
-
string|null|array|ExpressionInterface|callback
$append Expression or builder function to append.
-
string
$conjunction type of conjunction to be used to operate part
-
array
$types associative array of type names used to bind values to query
Returns
void
_decorateStatement() ¶ protected
_decorateStatement(Cake\Database\StatementInterface $statement): Cake\Database\Statement\CallbackStatement
Auxiliary function used to wrap the original statement from the driver with any registered callbacks.
Parameters
-
Cake\Database\StatementInterface
$statement to be decorated
Returns
Cake\Database\Statement\CallbackStatement
_dirty() ¶ protected
_dirty(): void
Marks a query as dirty, removing any preprocessed information from in memory caching.
Returns
void
_makeJoin() ¶ protected
_makeJoin(string|array $table, string|array|Cake\Database\ExpressionInterface $conditions, string $type): array
Returns an array that can be passed to the join method describing a single join clause
Parameters
-
string|array
$table The table to join with
-
string|array|Cake\Database\ExpressionInterface
$conditions The conditions to use for joining.
-
string
$type the join type to use
Returns
array
andHaving() ¶ public
andHaving(string|array|ExpressionInterface|callback $conditions, array $types = []): $this
Connects any previously defined set of conditions to the provided list
using the AND operator in the HAVING clause. This method operates in exactly
the same way as the method andWhere()
does. Please refer to its
documentation for an insight on how to using each parameter.
Parameters
-
string|array|ExpressionInterface|callback
$conditions The AND conditions for HAVING.
-
array
$types optional associative array of type names used to bind values to query
Returns
$this
See Also
andWhere() ¶ public
andWhere(string|array|ExpressionInterface|callback $conditions, array $types = []): $this
Connects any previously defined set of conditions to the provided list
using the AND operator. This function accepts the conditions list in the same
format as the method where
does, hence you can use arrays, expression objects
callback functions or strings.
It is important to notice that when calling this function, any previous set of conditions defined for this query will be treated as a single argument for the AND operator. This function will not only operate the most recently defined condition, but all the conditions as a whole.
When using an array for defining conditions, creating constraints form each
array entry will use the same logic as with the where()
function. This means
that each array entry will be joined to the other using the AND operator, unless
you nest the conditions in the array using other operator.
Examples:
$query->where(['title' => 'Hello World')->andWhere(['author_id' => 1]);
Will produce:
WHERE title = 'Hello World' AND author_id = 1
$query
->where(['OR' => ['published' => false, 'published is NULL']])
->andWhere(['author_id' => 1, 'comments_count >' => 10])
Produces:
WHERE (published = 0 OR published IS NULL) AND author_id = 1 AND comments_count > 10
$query
->where(['title' => 'Foo'])
->andWhere(function ($exp, $query) {
return $exp
->add(['author_id' => 1])
->or_(['author_id' => 2]);
});
Generates the following conditions:
WHERE (title = 'Foo') AND (author_id = 1 OR author_id = 2)
Parameters
-
string|array|ExpressionInterface|callback
$conditions The conditions to add with AND.
-
array
$types optional associative array of type names used to bind values to query
Returns
$this
See Also
\Cake\Database\Type
bind() ¶ public
bind(string|int $param, mixed $value, string|int $type = 'string'): $this
Associates a query placeholder to a value and a type.
If type is expressed as "atype[]" (note braces) then it will cause the placeholder to be re-written dynamically so if the value is an array, it will create as many placeholders as values are in it. For example "string[]" will create several placeholders of type string.
Parameters
-
string|int
$param placeholder to be replaced with quoted version of $value
-
mixed
$value The value to be bound
-
string|int
$type optional the mapped type name, used for casting when sending to database
Returns
$this
bufferResults() ¶ public
bufferResults(bool|null $enable = null): bool|$this
Enable/Disable buffered results.
When enabled the results returned by this Query will be buffered. This enables you to iterate a result set multiple times, or both cache and iterate it.
When disabled it will consume less memory as fetched results are not remembered for future iterations.
If called with no arguments, it will return whether or not buffering is enabled.
Parameters
-
bool|null
$enable optional whether or not to enable buffering
Returns
bool|$this
clause() ¶ public
clause(string $name): mixed
Returns any data that was stored in the specified clause. This is useful for modifying any internal part of the query and it is used by the SQL dialects to transform the query accordingly before it is executed. The valid clauses that can be retrieved are: delete, update, set, insert, values, select, distinct, from, join, set, where, group, having, order, limit, offset and union.
The return value for each of those parts may vary. Some clauses use QueryExpression to internally store their state, some use arrays and others may use booleans or integers. This is summary of the return types for each clause.
- update: string The name of the table to update
- set: QueryExpression
- insert: array, will return an array containing the table + columns.
- values: ValuesExpression
- select: array, will return empty array when no fields are set
- distinct: boolean
- from: array of tables
- join: array
- set: array
- where: QueryExpression, returns null when not set
- group: array
- having: QueryExpression, returns null when not set
- order: OrderByExpression, returns null when not set
- limit: integer or QueryExpression, null when not set
- offset: integer or QueryExpression, null when not set
- union: array
Parameters
-
string
$name name of the clause to be returned
Returns
mixed
connection() ¶ public
connection(Cake\Datasource\ConnectionInterface $connection = null): $this|Cake\Datasource\ConnectionInterface
Sets the connection instance to be used for executing and transforming this query When called with a null argument, it will return the current connection instance.
Parameters
-
Cake\Datasource\ConnectionInterface
$connection optional instance
Returns
$this|Cake\Datasource\ConnectionInterface
decorateResults() ¶ public
decorateResults(null|callable $callback, bool $overwrite = false): $this
Registers a callback to be executed for each result that is fetched from the result set, the callback function will receive as first parameter an array with the raw data from the database for every row that is fetched and must return the row with any possible modifications.
Callbacks will be executed lazily, if only 3 rows are fetched for database it will called 3 times, event though there might be more rows to be fetched in the cursor.
Callbacks are stacked in the order they are registered, if you wish to reset the stack the call this function with the second parameter set to true.
If you wish to remove all decorators from the stack, set the first parameter to null and the second to true.
Example
$query->decorateResults(function ($row) {
$row['order_total'] = $row['subtotal'] + ($row['subtotal'] * $row['tax']);
return $row;
});
Parameters
-
null|callable
$callback The callback to invoke when results are fetched.
-
bool
$overwrite optional Whether or not this should append or replace all existing decorators.
Returns
$this
defaultTypes() ¶ public
defaultTypes(array $types = null): $this|array
Allows setting default types when chaining query
Parameters
-
array
$types optional The array of types to set.
Returns
$this|array
delete() ¶ public
delete(string $table = null): $this
Create a delete query.
Can be combined with from(), where() and other methods to create delete queries with specific conditions.
Parameters
-
string
$table optional The table to use when deleting.
Returns
$this
distinct() ¶ public
distinct(array|ExpressionInterface|string|bool $on = [], bool $overwrite = false): $this
Adds a DISTINCT clause to the query to remove duplicates from the result set. This clause can only be used for select statements.
If you wish to filter duplicates based of those rows sharing a particular field or set of fields, you may pass an array of fields to filter on. Beware that this option might not be fully supported in all database systems.
Examples:
// Filters products with the same name and city
$query->select(['name', 'city'])->from('products')->distinct();
// Filters products in the same city
$query->distinct(['city']);
$query->distinct('city');
// Filter products with the same name
$query->distinct(['name'], true);
$query->distinct('name', true);
Parameters
-
array|ExpressionInterface|string|bool
$on optional Enable/disable distinct class or list of fields to be filtered on
-
bool
$overwrite optional whether to reset fields with passed list or not
Returns
$this
epilog() ¶ public
epilog(string|Cake\Database\Expression\QueryExpression $expression = null): $this
A string or expression that will be appended to the generated query
Examples:
$query->select('id')->where(['author_id' => 1])->epilog('FOR UPDATE');
$query
->insert('articles', ['title'])
->values(['author_id' => 1])
->epilog('RETURNING id');
Parameters
-
string|Cake\Database\Expression\QueryExpression
$expression optional The expression to be appended
Returns
$this
execute() ¶ public
execute(): Cake\Database\StatementInterface
Compiles the SQL representation of this query and executes it using the configured connection object. Returns the resulting statement object.
Executing a query internally executes several steps, the first one is letting the connection transform this object to fit its particular dialect, this might result in generating a different Query object that will be the one to actually be executed. Immediately after, literal values are passed to the connection so they are bound to the query in a safe way. Finally, the resulting statement is decorated with custom objects to execute callbacks for each row retrieved if necessary.
Resulting statement is traversable, so it can be used in any loop as you would with an array.
This method can be overridden in query subclasses to decorate behavior around query execution.
Returns
Cake\Database\StatementInterface
from() ¶ public
from(array|ExpressionInterface|string $tables = [], bool $overwrite = false): $this
Adds a single or multiple tables to be used in the FROM clause for this query. Tables can be passed as an array of strings, array of expression objects, a single expression or a single string.
If an array is passed, keys will be used to alias tables using the value as the real field to be aliased. It is possible to alias strings, ExpressionInterface objects or even other Query objects.
By default this function will append any passed argument to the list of tables to be selected from, unless the second argument is set to true.
This method can be used for select, update and delete statements.
Examples:
$query->from(['p' => 'posts']); // Produces FROM posts p
$query->from('authors'); // Appends authors: FROM posts p, authors
$query->from(['products'], true); // Resets the list: FROM products
$query->from(['sub' => $countQuery]); // FROM (SELECT ...) sub
Parameters
-
array|ExpressionInterface|string
$tables optional tables to be added to the list
-
bool
$overwrite optional whether to reset tables with passed list or not
Returns
$this
func() ¶ public
func(): Cake\Database\FunctionsBuilder
Returns an instance of a functions builder object that can be used for generating arbitrary SQL functions.
Example:
$query->func()->count('*');
$query->func()->dateDiff(['2012-01-05', '2012-01-02'])
Returns
Cake\Database\FunctionsBuilder
getIterator() ¶ public
getIterator(): Iterator
Executes this query and returns a results iterator. This function is required for implementing the IteratorAggregate interface and allows the query to be iterated without having to call execute() manually, thus making it look like a result set instead of the query itself.
Returns
Iterator
group() ¶ public
group(array|ExpressionInterface|string $fields, bool $overwrite = false): $this
Adds a single or multiple fields to be used in the GROUP BY clause for this query. Fields can be passed as an array of strings, array of expression objects, a single expression or a single string.
By default this function will append any passed argument to the list of fields to be grouped, unless the second argument is set to true.
Examples:
// Produces GROUP BY id, title
$query->group(['id', 'title']);
// Produces GROUP BY title
$query->group('title');
Parameters
-
array|ExpressionInterface|string
$fields fields to be added to the list
-
bool
$overwrite optional whether to reset fields with passed list or not
Returns
$this
having() ¶ public
having(string|array|ExpressionInterface|callback $conditions = null, array $types = [], bool $overwrite = false): $this
Adds a condition or set of conditions to be used in the HAVING clause for this
query. This method operates in exactly the same way as the method where()
does. Please refer to its documentation for an insight on how to using each
parameter.
Parameters
-
string|array|ExpressionInterface|callback
$conditions optional The having conditions.
-
array
$types optional associative array of type names used to bind values to query
-
bool
$overwrite optional whether to reset conditions with passed list or not
Returns
$this
See Also
innerJoin() ¶ public
innerJoin(string|array $table, string|array|Cake\Database\ExpressionInterface $conditions = [], array $types = []): $this
Adds a single INNER JOIN clause to the query.
This is a shorthand method for building joins via join()
.
The arguments of this method are identical to the leftJoin()
shorthand, please refer
to that methods description for further details.
Parameters
-
string|array
$table The table to join with
-
string|array|Cake\Database\ExpressionInterface
$conditions optional The conditions to use for joining.
-
array
$types optional a list of types associated to the conditions used for converting values to the corresponding database representation.
Returns
$this
insert() ¶ public
insert(array $columns, array $types = []): $this
Create an insert query.
Note calling this method will reset any data previously set with Query::values().
Parameters
-
array
$columns The columns to insert into.
-
array
$types optional A map between columns & their datatypes.
Returns
$this
Throws
RuntimeException
When there are 0 columns.
into() ¶ public
into(string $table): $this
Set the table name for insert queries.
Parameters
-
string
$table The table name to insert into.
Returns
$this
join() ¶ public
join(array|string|null $tables = null, array $types = [], bool $overwrite = false): $this
Adds a single or multiple tables to be used as JOIN clauses to this query. Tables can be passed as an array of strings, an array describing the join parts, an array with multiple join descriptions, or a single string.
By default this function will append any passed argument to the list of tables to be joined, unless the third argument is set to true.
When no join type is specified an INNER JOIN is used by default:
$query->join(['authors'])
will produce INNER JOIN authors ON 1 = 1
It is also possible to alias joins using the array key:
$query->join(['a' => 'authors'])`` will produce
INNER JOIN authors a ON 1 = 1`
A join can be fully described and aliased using the array notation:
$query->join([
'a' => [
'table' => 'authors',
'type' => 'LEFT',
'conditions' => 'a.id = b.author_id'
]
]);
// Produces LEFT JOIN authors a ON a.id = b.author_id
You can even specify multiple joins in an array, including the full description:
$query->join([
'a' => [
'table' => 'authors',
'type' => 'LEFT',
'conditions' => 'a.id = b.author_id'
],
'p' => [
'table' => 'publishers',
'type' => 'INNER',
'conditions' => 'p.id = b.publisher_id AND p.name = "Cake Software Foundation"'
]
]);
// LEFT JOIN authors a ON a.id = b.author_id
// INNER JOIN publishers p ON p.id = b.publisher_id AND p.name = "Cake Software Foundation"
Using conditions and types
Conditions can be expressed, as in the examples above, using a string for comparing columns, or string with already quoted literal values. Additionally it is possible to use conditions expressed in arrays or expression objects.
When using arrays for expressing conditions, it is often desirable to convert the literal values to the correct database representation. This is achieved using the second parameter of this function.
$query->join(['a' => [
'table' => 'articles',
'conditions' => [
'a.posted >=' => new DateTime('-3 days'),
'a.published' => true,
'a.author_id = authors.id'
]
]], ['a.posted' => 'datetime', 'a.published' => 'boolean'])
Overwriting joins
When creating aliased joins using the array notation, you can override previous join definitions by using the same alias in consequent calls to this function or you can replace all previously defined joins with another list if the third parameter for this function is set to true.
$query->join(['alias' => 'table']); // joins table with as alias
$query->join(['alias' => 'another_table']); // joins another_table with as alias
$query->join(['something' => 'different_table'], [], true); // resets joins list
Parameters
-
array|string|null
$tables optional list of tables to be joined in the query
-
array
$types optional associative array of type names used to bind values to query
-
bool
$overwrite optional whether to reset joins with passed list or not
Returns
$this
See Also
leftJoin() ¶ public
leftJoin(string|array $table, string|array|Cake\Database\ExpressionInterface $conditions = [], array $types = []): $this
Adds a single LEFT JOIN clause to the query.
This is a shorthand method for building joins via join()
.
The table name can be passed as a string, or as an array in case it needs to be aliased:
// LEFT JOIN authors ON authors.id = posts.author_id
$query->leftJoin('authors', 'authors.id = posts.author_id');
// LEFT JOIN authors a ON a.id = posts.author_id
$query->leftJoin(['a' => 'authors'], 'a.id = posts.author_id');
Conditions can be passed as strings, arrays, or expression objects. When
using arrays it is possible to combine them with the $types
parameter
in order to define how to convert the values:
$query->leftJoin(['a' => 'articles'], [
'a.posted >=' => new DateTime('-3 days'),
'a.published' => true,
'a.author_id = authors.id'
], ['a.posted' => 'datetime', 'a.published' => 'boolean']);
See join()
for further details on conditions and types.
Parameters
-
string|array
$table The table to join with
-
string|array|Cake\Database\ExpressionInterface
$conditions optional The conditions to use for joining.
-
array
$types optional a list of types associated to the conditions used for converting values to the corresponding database representation.
Returns
$this
limit() ¶ public
limit(int|ExpressionInterface $num): $this
Sets the number of records that should be retrieved from database, accepts an integer or an expression object that evaluates to an integer. In some databases, this operation might not be supported or will require the query to be transformed in order to limit the result set size.
Examples
$query->limit(10) // generates LIMIT 10
$query->limit($query->newExpr()->add(['1 + 1'])); // LIMIT (1 + 1)
Parameters
-
int|ExpressionInterface
$num number of records to be returned
Returns
$this
modifier() ¶ public
modifier(array|ExpressionInterface|string $modifiers, bool $overwrite = false): $this
Adds a single or multiple SELECT modifiers to be used in the SELECT.
By default this function will append any passed argument to the list of modifiers to be applied, unless the second argument is set to true.
Example:
// Ignore cache query in MySQL
$query->select(['name', 'city'])->from('products')->modifier('SQL_NO_CACHE');
// It will produce the SQL: SELECT SQL_NO_CACHE name, city FROM products
// Or with multiple modifiers
$query->select(['name', 'city'])->from('products')->modifier(['HIGH_PRIORITY', 'SQL_NO_CACHE']);
// It will produce the SQL: SELECT HIGH_PRIORITY SQL_NO_CACHE name, city FROM products
Parameters
-
array|ExpressionInterface|string
$modifiers modifiers to be applied to the query
-
bool
$overwrite optional whether to reset order with field list or not
Returns
$this
newExpr() ¶ public
newExpr(mixed $rawExpression = null): Cake\Database\Expression\QueryExpression
Returns a new QueryExpression object. This is a handy function when building complex queries using a fluent interface. You can also override this function in subclasses to use a more specialized QueryExpression class if required.
You can optionally pass a single raw SQL string or an array or expressions in any format accepted by \Cake\Database\Expression\QueryExpression:
$expression = $query->newExpr(); // Returns an empty expression object
$expression = $query->newExpr('Table.column = Table2.column'); // Return a raw SQL expression
Parameters
-
mixed
$rawExpression optional A string, array or anything you want wrapped in an expression object
Returns
Cake\Database\Expression\QueryExpression
offset() ¶ public
offset(int|ExpressionInterface $num): $this
Sets the number of records that should be skipped from the original result set This is commonly used for paginating large results. Accepts an integer or an expression object that evaluates to an integer.
In some databases, this operation might not be supported or will require the query to be transformed in order to limit the result set size.
Examples
$query->offset(10) // generates OFFSET 10
$query->offset($query->newExpr()->add(['1 + 1'])); // OFFSET (1 + 1)
Parameters
-
int|ExpressionInterface
$num number of records to be skipped
Returns
$this
orHaving() ¶ public
orHaving(string|array|ExpressionInterface|callback $conditions, array $types = []): $this
Connects any previously defined set of conditions to the provided list
using the OR operator in the HAVING clause. This method operates in exactly
the same way as the method orWhere()
does. Please refer to its
documentation for an insight on how to using each parameter.
Parameters
-
string|array|ExpressionInterface|callback
$conditions The OR conditions for HAVING.
-
array
$types optional associative array of type names used to bind values to query.
Returns
$this
See Also
orWhere() ¶ public
orWhere(string|array|ExpressionInterface|callback $conditions, array $types = []): $this
Connects any previously defined set of conditions to the provided list
using the OR operator. This function accepts the conditions list in the same
format as the method where
does, hence you can use arrays, expression objects
callback functions or strings.
It is important to notice that when calling this function, any previous set of conditions defined for this query will be treated as a single argument for the OR operator. This function will not only operate the most recently defined condition, but all the conditions as a whole.
When using an array for defining conditions, creating constraints form each
array entry will use the same logic as with the where()
function. This means
that each array entry will be joined to the other using the OR operator, unless
you nest the conditions in the array using other operator.
Examples:
$query->where(['title' => 'Hello World')->orWhere(['title' => 'Foo']);
Will produce:
WHERE title = 'Hello World' OR title = 'Foo'
$query
->where(['OR' => ['published' => false, 'published is NULL']])
->orWhere(['author_id' => 1, 'comments_count >' => 10])
Produces:
WHERE (published = 0 OR published IS NULL) OR (author_id = 1 AND comments_count > 10)
$query
->where(['title' => 'Foo'])
->orWhere(function ($exp, $query) {
return $exp
->add(['author_id' => 1])
->or_(['author_id' => 2]);
});
Generates the following conditions:
WHERE (title = 'Foo') OR (author_id = 1 OR author_id = 2)
Parameters
-
string|array|ExpressionInterface|callback
$conditions The conditions to add with OR.
-
array
$types optional associative array of type names used to bind values to query
Returns
$this
See Also
\Cake\Database\Type
order() ¶ public
order(array|Cake\Database\ExpressionInterface|string $fields, bool $overwrite = false): $this
Adds a single or multiple fields to be used in the ORDER clause for this query. Fields can be passed as an array of strings, array of expression objects, a single expression or a single string.
If an array is passed, keys will be used as the field itself and the value will represent the order in which such field should be ordered. When called multiple times with the same fields as key, the last order definition will prevail over the others.
By default this function will append any passed argument to the list of fields to be selected, unless the second argument is set to true.
Examples:
$query->order(['title' => 'DESC', 'author_id' => 'ASC']);
Produces:
ORDER BY title DESC, author_id ASC
$query->order(['title' => 'DESC NULLS FIRST'])->order('author_id');
Will generate:
ORDER BY title DESC NULLS FIRST, author_id
$expression = $query->newExpr()->add(['id % 2 = 0']);
$query->order($expression)->order(['title' => 'ASC']);
Will become:
ORDER BY (id %2 = 0), title ASC
If you need to set complex expressions as order conditions, you
should use orderAsc()
or orderDesc()
.
Parameters
-
array|Cake\Database\ExpressionInterface|string
$fields fields to be added to the list
-
bool
$overwrite optional whether to reset order with field list or not
Returns
$this
orderAsc() ¶ public
orderAsc(string|Cake\Database\Expression\QueryExpression $field, bool $overwrite = false): $this
Add an ORDER BY clause with an ASC direction.
This method allows you to set complex expressions as order conditions unlike order()
Parameters
-
string|Cake\Database\Expression\QueryExpression
$field The field to order on.
-
bool
$overwrite optional Whether or not to reset the order clauses.
Returns
$this
orderDesc() ¶ public
orderDesc(string|Cake\Database\Expression\QueryExpression $field, bool $overwrite = false): $this
Add an ORDER BY clause with an ASC direction.
This method allows you to set complex expressions as order conditions unlike order()
Parameters
-
string|Cake\Database\Expression\QueryExpression
$field The field to order on.
-
bool
$overwrite optional Whether or not to reset the order clauses.
Returns
$this
page() ¶ public
page(int $num, int $limit = null): $this
Set the page of results you want.
This method provides an easier to use interface to set the limit + offset
in the record set you want as results. If empty the limit will default to
the existing limit clause, and if that too is empty, then 25
will be used.
Pages should start at 1.
Parameters
-
int
$num The page number you want.
-
int
$limit optional The number of rows you want in the page. If null the current limit clause will be used.
Returns
$this
removeJoin() ¶ public
removeJoin(string $name): $this
Remove a join if it has been defined.
Useful when you are redefining joins or want to re-order the join clauses.
Parameters
-
string
$name The alias/name of the join to remove.
Returns
$this
rightJoin() ¶ public
rightJoin(string|array $table, string|array|Cake\Database\ExpressionInterface $conditions = [], array $types = []): $this
Adds a single RIGHT JOIN clause to the query.
This is a shorthand method for building joins via join()
.
The arguments of this method are identical to the leftJoin()
shorthand, please refer
to that methods description for further details.
Parameters
-
string|array
$table The table to join with
-
string|array|Cake\Database\ExpressionInterface
$conditions optional The conditions to use for joining.
-
array
$types optional a list of types associated to the conditions used for converting values to the corresponding database representation.
Returns
$this
select() ¶ public
select(array|ExpressionInterface|string|callable $fields = [], bool $overwrite = false): $this
Adds new fields to be returned by a SELECT statement when this query is executed. Fields can be passed as an array of strings, array of expression objects, a single expression or a single string.
If an array is passed, keys will be used to alias fields using the value as the real field to be aliased. It is possible to alias strings, Expression objects or even other Query objects.
If a callable function is passed, the returning array of the function will be used as the list of fields.
By default this function will append any passed argument to the list of fields to be selected, unless the second argument is set to true.
Examples:
$query->select(['id', 'title']); // Produces SELECT id, title
$query->select(['author' => 'author_id']); // Appends author: SELECT id, title, author_id as author
$query->select('id', true); // Resets the list: SELECT id
$query->select(['total' => $countQuery]); // SELECT id, (SELECT ...) AS total
$query->select(function ($query) {
return ['article_id', 'total' => $query->count('*')];
})
By default no fields are selected, if you have an instance of Cake\ORM\Query
and try to append
fields you should also call Cake\ORM\Query::autoFields()
to select the default fields
from the table.
Parameters
-
array|ExpressionInterface|string|callable
$fields optional fields to be added to the list.
-
bool
$overwrite optional whether to reset fields with passed list or not
Returns
$this
set() ¶ public
set(string|array|callable|QueryExpression $key, mixed $value = null, array $types = []): $this
Set one or many fields to update.
Examples
Passing a string:
$query->update('articles')->set('title', 'The Title');
Passing an array:
$query->update('articles')->set(['title' => 'The Title'], ['title' => 'string']);
Passing a callable:
$query->update('articles')->set(function ($exp) {
return $exp->eq('title', 'The title', 'string');
});
Parameters
-
string|array|callable|QueryExpression
$key The column name or array of keys
- values to set. This can also be a QueryExpression containing a SQL fragment. It can also be a callable, that is required to return an expression object.
-
mixed
$value optional The value to update $key to. Can be null if $key is an array or QueryExpression. When $key is an array, this parameter will be used as $types instead.
-
array
$types optional The column types to treat data as.
Returns
$this
sql() ¶ public
sql(Cake\Database\ValueBinder $generator = null): string
Returns the SQL representation of this object.
This function will compile this query to make it compatible with the SQL dialect that is used by the connection, This process might add, remove or alter any query part or internal expression to make it executable in the target platform.
The resulting query may have placeholders that will be replaced with the actual values when the query is executed, hence it is most suitable to use with prepared statements.
Parameters
-
Cake\Database\ValueBinder
$generator optional A placeholder object that will hold associated values for expressions
Returns
string
traverse() ¶ public
traverse(callable $visitor, array $parts = []): $this
Will iterate over every specified part. Traversing functions can aggregate results using variables in the closure or instance variables. This function is commonly used as a way for traversing all query parts that are going to be used for constructing a query.
The callback will receive 2 parameters, the first one is the value of the query part that is being iterated and the second the name of such part.
Example:
$query->select(['title'])->from('articles')->traverse(function ($value, $clause) {
if ($clause === 'select') {
var_dump($value);
}
}, ['select', 'from']);
Parameters
-
callable
$visitor a function or callable to be executed for each part
-
array
$parts optional the query clauses to traverse
Returns
$this
traverseExpressions() ¶ public
traverseExpressions(callable $callback): $this|null
This function works similar to the traverse() function, with the difference that it does a full depth traversal of the entire expression tree. This will execute the provided callback function for each ExpressionInterface object that is stored inside this query at any nesting depth in any part of the query.
Callback will receive as first parameter the currently visited expression.
Parameters
-
callable
$callback the function to be executed for each ExpressionInterface found inside this query.
Returns
$this|null
type() ¶ public
type(): string
Returns the type of this query (select, insert, update, delete)
Returns
string
typeMap() ¶ public
typeMap(array|TypeMap $typeMap = null): $this|TypeMap
Creates a new TypeMap if $typeMap is an array, otherwise returns the existing type map or exchanges it for the given one.
Parameters
-
array|TypeMap
$typeMap optional Creates a TypeMap if array, otherwise sets the given TypeMap
Returns
$this|TypeMap
union() ¶ public
union(string|Query $query, bool $overwrite = false): $this
Adds a complete query to be used in conjunction with an UNION operator with this query. This is used to combine the result set of this query with the one that will be returned by the passed query. You can add as many queries as you required by calling multiple times this method with different queries.
By default, the UNION operator will remove duplicate rows, if you wish to include every row for all queries, use unionAll().
Examples
$union = (new Query($conn))->select(['id', 'title'])->from(['a' => 'articles']);
$query->select(['id', 'name'])->from(['d' => 'things'])->union($union);
Will produce:
SELECT id, name FROM things d UNION SELECT id, title FROM articles a
Parameters
-
string|Query
$query full SQL query to be used in UNION operator
-
bool
$overwrite optional whether to reset the list of queries to be operated or not
Returns
$this
unionAll() ¶ public
unionAll(string|Query $query, bool $overwrite = false): $this
Adds a complete query to be used in conjunction with the UNION ALL operator with this query. This is used to combine the result set of this query with the one that will be returned by the passed query. You can add as many queries as you required by calling multiple times this method with different queries.
Unlike UNION, UNION ALL will not remove duplicate rows.
$union = (new Query($conn))->select(['id', 'title'])->from(['a' => 'articles']);
$query->select(['id', 'name'])->from(['d' => 'things'])->unionAll($union);
Will produce:
SELECT id, name FROM things d UNION ALL SELECT id, title FROM articles a
Parameters
-
string|Query
$query full SQL query to be used in UNION operator
-
bool
$overwrite optional whether to reset the list of queries to be operated or not
Returns
$this
update() ¶ public
update(string $table): $this
Create an update query.
Can be combined with set() and where() methods to create update queries.
Parameters
-
string
$table The table you want to update.
Returns
$this
valueBinder() ¶ public
valueBinder(Cake\Database\ValueBinder $binder = null): $this|Cake\Database\ValueBinder
Returns the currently used ValueBinder instance. If a value is passed, it will be set as the new instance to be used.
A ValueBinder is responsible for generating query placeholders and temporarily associate values to those placeholders so that they can be passed correctly statement object.
Parameters
-
Cake\Database\ValueBinder
$binder optional new instance to be set. If no value is passed the default one will be returned
Returns
$this|Cake\Database\ValueBinder
values() ¶ public
values(array|Query $data): $this
Set the values for an insert query.
Multi inserts can be performed by calling values() more than one time, or by providing an array of value sets. Additionally $data can be a Query instance to insert data from another SELECT statement.
Parameters
-
array|Query
$data The data to insert.
Returns
$this
Throws
Cake\Database\Exception
if you try to set values before declaring columns. Or if you try to set values on non-insert queries.
where() ¶ public
where(string|array|Cake\Database\ExpressionInterface|callback|null $conditions = null, array $types = [], bool $overwrite = false): $this
Adds a condition or set of conditions to be used in the WHERE clause for this query. Conditions can be expressed as an array of fields as keys with comparison operators in it, the values for the array will be used for comparing the field to such literal. Finally, conditions can be expressed as a single string or an array of strings.
When using arrays, each entry will be joined to the rest of the conditions using an AND operator. Consecutive calls to this function will also join the new conditions specified using the AND operator. Additionally, values can be expressed using expression objects which can include other query objects.
Any conditions created with this methods can be used with any SELECT, UPDATE and DELETE type of queries.
Conditions using operators:
$query->where([
'posted >=' => new DateTime('3 days ago'),
'title LIKE' => 'Hello W%',
'author_id' => 1,
], ['posted' => 'datetime']);
The previous example produces:
WHERE posted >= 2012-01-27 AND title LIKE 'Hello W%' AND author_id = 1
Second parameter is used to specify what type is expected for each passed key. Valid types can be used from the mapped with Database\Type class.
Nesting conditions with conjunctions:
$query->where([
'author_id !=' => 1,
'OR' => ['published' => true, 'posted <' => new DateTime('now')],
'NOT' => ['title' => 'Hello']
], ['published' => boolean, 'posted' => 'datetime']
The previous example produces:
WHERE author_id = 1 AND (published = 1 OR posted < '2012-02-01') AND NOT (title = 'Hello')
You can nest conditions using conjunctions as much as you like. Sometimes, you may want to define 2 different options for the same key, in that case, you can wrap each condition inside a new array:
$query->where(['OR' => [['published' => false], ['published' => true]])
Keep in mind that every time you call where() with the third param set to false (default), it will join the passed conditions to the previous stored list using the AND operator. Also, using the same array key twice in consecutive calls to this method will not override the previous value.
Using expressions objects:
$exp = $query->newExpr()->add(['id !=' => 100, 'author_id' != 1])->type('OR');
$query->where(['published' => true], ['published' => 'boolean'])->where($exp);
The previous example produces:
WHERE (id != 100 OR author_id != 1) AND published = 1
Other Query objects that be used as conditions for any field.
Adding conditions in multiple steps:
You can use callable functions to construct complex expressions, functions receive as first argument a new QueryExpression object and this query instance as second argument. Functions must return an expression object, that will be added the list of conditions for the query using the AND operator.
$query
->where(['title !=' => 'Hello World'])
->where(function ($exp, $query) {
$or = $exp->or_(['id' => 1]);
$and = $exp->and_(['id >' => 2, 'id <' => 10]);
return $or->add($and);
});
- The previous example produces:
WHERE title != 'Hello World' AND (id = 1 OR (id > 2 AND id < 10))
Conditions as strings:
$query->where(['articles.author_id = authors.id', 'modified IS NULL']);
The previous example produces:
WHERE articles.author_id = authors.id AND modified IS NULL
Please note that when using the array notation or the expression objects, all values will be correctly quoted and transformed to the correspondent database data type automatically for you, thus securing your application from SQL injections. If you use string conditions make sure that your values are correctly quoted. The safest thing you can do is to never use string conditions.
Parameters
-
string|array|Cake\Database\ExpressionInterface|callback|null
$conditions optional The conditions to filter on.
-
array
$types optional associative array of type names used to bind values to query
-
bool
$overwrite optional whether to reset conditions with passed list or not
Returns
$this
See Also
\Cake\Database\Expression\QueryExpression
Property Detail
$_connection ¶ protected
Connection instance to be used to execute this query.
Type
Cake\Datasource\ConnectionInterface
$_dirty ¶ protected
Indicates whether internal state of this query was changed, this is used to discard internal cached objects such as the transformed query or the reference to the executed statement.
Type
bool
$_functionsBuilder ¶ protected
Instance of functions builder object used for generating arbitrary SQL functions.
Type
FunctionsBuilder
$_iterator ¶ protected
Statement object resulting from executing this query.
Type
Cake\Database\StatementInterface
$_resultDecorators ¶ protected
A list of callback functions to be called to alter each row from resulting statement upon retrieval. Each one of the callback function will receive the row array as first argument.
Type
array
$_useBufferedResults ¶ protected
Boolean for tracking whether or not buffered results are enabled.
Type
bool
$_valueBinder ¶ protected
The object responsible for generating query placeholders and temporarily store values associated to each of those.
Type
ValueBinder