Class Query

Constructor.

Parameters

Returns an array that can be used to describe the internal state of this object.

Returns

Returns string representation of this query (complete SQL statement).

Returns

Helper function used to build conditions by composing QueryExpression objects.

Parameters

Returns

Auxiliary function used to wrap the original statement from the driver with any registered callbacks.

Parameters

Returns

Marks a query as dirty, removing any preprocessed information from in memory caching.

Returns

Returns an array that can be passed to the join method describing a single join clause

Parameters

Returns

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

Returns

See Also

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

Returns

See Also

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

Returns

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

Returns

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

Returns

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

Returns

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

Returns

Allows setting default types when chaining query

Parameters

Returns

Create a delete query.

Can be combined with from(), where() and other methods to create delete queries with specific conditions.

Parameters

Returns

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']);

// Filter products with the same name
$query->distinct(['name'], true);

Parameters

Returns

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

Returns

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

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->select(['products'], true); // Resets the list: FROM products
 $query->select(['sub' => $countQuery]); // FROM (SELECT ...) sub

Parameters

Returns

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

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

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

Returns

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

Returns

See Also

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

Returns

Create an insert query.

Note calling this method will reset any data previously set with Query::values().

Parameters

Returns

Throws

Set the table name for insert queries.

Parameters

Returns

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

Returns

See Also

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

Returns

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

Returns

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

Returns

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

Returns

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

Returns

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

Returns

See Also

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

Returns

See Also

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

Returns

Add an ORDER BY clause with an ASC direction.

This method allows you to set complex expressions as order conditions unlike order()

Parameters

Returns

Add an ORDER BY clause with an ASC direction.

This method allows you to set complex expressions as order conditions unlike order()

Parameters

Returns

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

Returns

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

Returns

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.

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

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

Returns

Set one or many fields to update.

Parameters

Returns

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

Returns

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

Returns

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

Returns

Returns the type of this query (select, insert, update, delete)

Returns

Creates a new TypeMap if $typeMap is an array, otherwise returns the existing type map or exchanges it for the given one.

Parameters

Returns

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

Returns

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

Returns

Create an update query.

Can be combined with set() and where() methods to create update queries.

Parameters

Returns

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

Returns

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

Returns

Throws

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

Returns

See Also