Class yii\db\Query

Inheritanceyii\db\Query » yii\base\Component » yii\base\Object
Implementsyii\base\Configurable, yii\db\QueryInterface
Uses Traitsyii\db\QueryTrait
Subclassesyii\db\ActiveQuery, yii\sphinx\ActiveQuery, yii\sphinx\Query
Available since version2.0
Source Code https://github.com/yiisoft/yii2/blob/master/framework/db/Query.php

Query represents a SELECT SQL statement in a way that is independent of DBMS.

Query provides a set of methods to facilitate the specification of different clauses in a SELECT statement. These methods can be chained together.

By calling createCommand(), we can get a yii\db\Command instance which can be further used to perform/execute the DB query against a database.

For example,

$query = new Query;
// compose the query
$query->select('id, name')
    ->from('user')
    ->limit(10);
// build and execute the query
$rows = $query->all();
// alternatively, you can create DB command and execute it
$command = $query->createCommand();
// $command->sql returns the actual SQL
$rows = $command->queryAll();

Query internally uses the yii\db\QueryBuilder class to generate the SQL statement.

A more detailed usage guide on how to work with Query can be found in the guide article on Query Builder.

Public Properties

Hide inherited properties

PropertyTypeDescriptionDefined By
$behaviors yii\base\Behavior[] List of behaviors attached to this component yii\base\Component
$distinct boolean Whether to select distinct rows of data only. yii\db\Query
$emulateExecution boolean Whether to emulate the actual query execution, returning empty or false results. yii\db\QueryTrait
$from array The table(s) to be selected from. yii\db\Query
$groupBy array How to group the query results. yii\db\Query
$having string|array|yii\db\Expression The condition to be applied in the GROUP BY clause. yii\db\Query
$indexBy string|callable The name of the column by which the query results should be indexed by. yii\db\QueryTrait
$join array How to join with other tables. yii\db\Query
$limit integer Maximum number of records to be returned. yii\db\QueryTrait
$offset integer Zero-based offset from where the records are to be returned. yii\db\QueryTrait
$orderBy array How to sort the query results. yii\db\QueryTrait
$params array List of query parameter values indexed by parameter placeholders. yii\db\Query
$select array The columns being selected. yii\db\Query
$selectOption string Additional option that should be appended to the 'SELECT' keyword. yii\db\Query
$union array This is used to construct the UNION clause(s) in a SQL statement. yii\db\Query
$where string|array Query condition. yii\db\QueryTrait

Public Methods

Hide inherited methods

MethodDescriptionDefined By
__call() Calls the named method which is not a class method. yii\base\Component
__clone() This method is called after the object is created by cloning an existing one. yii\base\Component
__construct() Constructor. yii\base\Object
__get() Returns the value of a component property. yii\base\Component
__isset() Checks if a property is set, i.e. defined and not null. yii\base\Component
__set() Sets the value of a component property. yii\base\Component
__unset() Sets a component property to be null. yii\base\Component
addGroupBy() Adds additional group-by columns to the existing ones. yii\db\Query
addOrderBy() Adds additional ORDER BY columns to the query. yii\db\QueryTrait
addParams() Adds additional parameters to be bound to the query. yii\db\Query
addSelect() Add more columns to the SELECT part of the query. yii\db\Query
all() Executes the query and returns all results as an array. yii\db\Query
andFilterCompare() Adds a filtering condition for a specific column and allow the user to choose a filter operator. yii\db\Query
andFilterHaving() Adds an additional HAVING condition to the existing one but ignores empty operands. yii\db\Query
andFilterWhere() Adds an additional WHERE condition to the existing one but ignores empty operands. yii\db\QueryTrait
andHaving() Adds an additional HAVING condition to the existing one. yii\db\Query
andWhere() Adds an additional WHERE condition to the existing one. yii\db\Query
attachBehavior() Attaches a behavior to this component. yii\base\Component
attachBehaviors() Attaches a list of behaviors to the component. yii\base\Component
average() Returns the average of the specified column values. yii\db\Query
batch() Starts a batch query. yii\db\Query
behaviors() Returns a list of behaviors that this component should behave as. yii\base\Component
canGetProperty() Returns a value indicating whether a property can be read. yii\base\Component
canSetProperty() Returns a value indicating whether a property can be set. yii\base\Component
className() Returns the fully qualified name of this class. yii\base\Object
column() Executes the query and returns the first column of the result. yii\db\Query
count() Returns the number of records. yii\db\Query
create() Creates a new Query object and copies its property values from an existing one. yii\db\Query
createCommand() Creates a DB command that can be used to execute this query. yii\db\Query
detachBehavior() Detaches a behavior from the component. yii\base\Component
detachBehaviors() Detaches all behaviors from the component. yii\base\Component
distinct() Sets the value indicating whether to SELECT DISTINCT or not. yii\db\Query
each() Starts a batch query and retrieves data row by row. yii\db\Query
emulateExecution() Sets whether to emulate query execution, preventing any interaction with data storage. yii\db\QueryTrait
ensureBehaviors() Makes sure that the behaviors declared in behaviors() are attached to this component. yii\base\Component
exists() Returns a value indicating whether the query result contains any row of data. yii\db\Query
filterHaving() Sets the HAVING part of the query but ignores empty operands. yii\db\Query
filterWhere() Sets the WHERE part of the query but ignores empty operands. yii\db\QueryTrait
from() Sets the FROM part of the query. yii\db\Query
getBehavior() Returns the named behavior object. yii\base\Component
getBehaviors() Returns all behaviors attached to this component. yii\base\Component
groupBy() Sets the GROUP BY part of the query. yii\db\Query
hasEventHandlers() Returns a value indicating whether there is any handler attached to the named event. yii\base\Component
hasMethod() Returns a value indicating whether a method is defined. yii\base\Component
hasProperty() Returns a value indicating whether a property is defined for this component. yii\base\Component
having() Sets the HAVING part of the query. yii\db\Query
indexBy() Sets the indexBy() property. yii\db\QueryTrait
init() Initializes the object. yii\base\Object
innerJoin() Appends an INNER JOIN part to the query. yii\db\Query
join() Appends a JOIN part to the query. yii\db\Query
leftJoin() Appends a LEFT OUTER JOIN part to the query. yii\db\Query
limit() Sets the LIMIT part of the query. yii\db\QueryTrait
max() Returns the maximum of the specified column values. yii\db\Query
min() Returns the minimum of the specified column values. yii\db\Query
off() Detaches an existing event handler from this component. yii\base\Component
offset() Sets the OFFSET part of the query. yii\db\QueryTrait
on() Attaches an event handler to an event. yii\base\Component
one() Executes the query and returns a single row of result. yii\db\Query
orFilterHaving() Adds an additional HAVING condition to the existing one but ignores empty operands. yii\db\Query
orFilterWhere() Adds an additional WHERE condition to the existing one but ignores empty operands. yii\db\QueryTrait
orHaving() Adds an additional HAVING condition to the existing one. yii\db\Query
orWhere() Adds an additional WHERE condition to the existing one. yii\db\Query
orderBy() Sets the ORDER BY part of the query. yii\db\QueryTrait
params() Sets the parameters to be bound to the query. yii\db\Query
populate() Converts the raw query results into the format as specified by this query. yii\db\Query
prepare() Prepares for building SQL. yii\db\Query
rightJoin() Appends a RIGHT OUTER JOIN part to the query. yii\db\Query
scalar() Returns the query result as a scalar value. yii\db\Query
select() Sets the SELECT part of the query. yii\db\Query
sum() Returns the sum of the specified column values. yii\db\Query
trigger() Triggers an event. yii\base\Component
union() Appends a SQL statement using UNION operator. yii\db\Query
where() Sets the WHERE part of the query. yii\db\Query

Protected Methods

Hide inherited methods

MethodDescriptionDefined By
filterCondition() Removes empty operands from the given query condition. yii\db\QueryTrait
isEmpty() Returns a value indicating whether the give value is "empty". yii\db\QueryTrait
normalizeOrderBy() Normalizes format of ORDER BY data yii\db\QueryTrait
queryScalar() Queries a scalar value by setting select() first. yii\db\Query

Property Details

$distinct public property

Whether to select distinct rows of data only. If this is set true, the SELECT clause would be changed to SELECT DISTINCT.

public boolean $distinct null
$from public property

The table(s) to be selected from. For example, ['user', 'post']. This is used to construct the FROM clause in a SQL statement.

See also from().

public array $from null
$groupBy public property

How to group the query results. For example, ['company', 'department']. This is used to construct the GROUP BY clause in a SQL statement.

public array $groupBy null
$having public property

The condition to be applied in the GROUP BY clause. It can be either a string or an array. Please refer to where() on how to specify the condition.

$join public property

How to join with other tables. Each array element represents the specification of one join which has the following structure:

[$joinType, $tableName, $joinCondition]

For example,

[
    ['INNER JOIN', 'user', 'user.id = author_id'],
    ['LEFT JOIN', 'team', 'team.id = team_id'],
]
public array $join null
$params public property

List of query parameter values indexed by parameter placeholders. For example, [':name' => 'Dan', ':age' => 31].

public array $params = []
$select public property

The columns being selected. For example, ['id', 'name']. This is used to construct the SELECT clause in a SQL statement. If not set, it means selecting all columns.

See also select().

public array $select null
$selectOption public property

Additional option that should be appended to the 'SELECT' keyword. For example, in MySQL, the option 'SQL_CALC_FOUND_ROWS' can be used.

public string $selectOption null
$union public property

This is used to construct the UNION clause(s) in a SQL statement. Each array element is an array of the following structure:

  • query: either a string or a yii\db\Query object representing a query
  • all: boolean, whether it should be UNION ALL or UNION
public array $union null

Method Details

addGroupBy() public method

Adds additional group-by columns to the existing ones.

See also groupBy().

public $this addGroupBy ( $columns )
$columns string|array

Additional columns to be grouped by. Columns can be specified in either a string (e.g. "id, name") or an array (e.g. ['id', 'name']). The method will automatically quote the column names unless a column contains some parenthesis (which means the column contains a DB expression).

Note that if your group-by is an expression containing commas, you should always use an array to represent the group-by information. Otherwise, the method will not be able to correctly determine the group-by columns.

Since version 2.0.7, an yii\db\Expression object can be passed to specify the GROUP BY part explicitly in plain SQL.

return $this

The query object itself

addParams() public method

Adds additional parameters to be bound to the query.

See also params().

public $this addParams ( $params )
$params array

List of query parameter values indexed by parameter placeholders. For example, [':name' => 'Dan', ':age' => 31].

return $this

The query object itself

addSelect() public method

Add more columns to the SELECT part of the query.

Note, that if select() has not been specified before, you should include * explicitly if you want to select all remaining columns too:

$query->addSelect(["*", "CONCAT(first_name, ' ', last_name) AS full_name"])->one();

See also select().

public $this addSelect ( $columns )
$columns string|array|yii\db\Expression

The columns to add to the select. See select() for more details about the format of this parameter.

return $this

The query object itself

all() public method

Executes the query and returns all results as an array.

public array all ( $db null )
$db yii\db\Connection

The database connection used to generate the SQL statement. If this parameter is not given, the db application component will be used.

return array

The query results. If the query results in nothing, an empty array will be returned.

andFilterCompare() public method (available since version 2.0.8)

Adds a filtering condition for a specific column and allow the user to choose a filter operator.

It adds an additional WHERE condition for the given field and determines the comparison operator based on the first few characters of the given value. The condition is added in the same way as in andFilterWhere() so empty values are ignored. The new condition and the existing one will be joined using the AND operator.

The comparison operator is intelligently determined based on the first few characters in the given value. In particular, it recognizes the following operators if they appear as the leading characters in the given value:

  • <: the column must be less than the given value.
  • >: the column must be greater than the given value.
  • <=: the column must be less than or equal to the given value.
  • >=: the column must be greater than or equal to the given value.
  • <>: the column must not be the same as the given value.
  • =: the column must be equal to the given value.
  • If none of the above operators is detected, the $defaultOperator will be used.
public $this andFilterCompare ( $name, $value, $defaultOperator '=' )
$name string

The column name.

$value string

The column value optionally prepended with the comparison operator.

$defaultOperator string

The operator to use, when no operator is given in $value. Defaults to =, performing an exact match.

return $this

The query object itself

andFilterHaving() public method (available since version 2.0.11)

Adds an additional HAVING condition to the existing one but ignores empty operands.

The new condition and the existing one will be joined using the AND operator.

This method is similar to andHaving(). The main difference is that this method will remove empty query operands. As a result, this method is best suited for building query conditions based on filter values entered by users.

See also:

public $this andFilterHaving ( array $condition )
$condition array

The new HAVING condition. Please refer to having() on how to specify this parameter.

return $this

The query object itself

andHaving() public method

Adds an additional HAVING condition to the existing one.

The new condition and the existing one will be joined using the AND operator.

See also:

public $this andHaving ( $condition, $params = [] )
$condition string|array|yii\db\Expression

The new HAVING condition. Please refer to where() on how to specify this parameter.

$params array

The parameters (name => value) to be bound to the query.

return $this

The query object itself

andWhere() public method

Adds an additional WHERE condition to the existing one.

The new condition and the existing one will be joined using the AND operator.

See also:

public $this andWhere ( $condition, $params = [] )
$condition string|array|yii\db\Expression

The new WHERE condition. Please refer to where() on how to specify this parameter.

$params array

The parameters (name => value) to be bound to the query.

return $this

The query object itself

average() public method

Returns the average of the specified column values.

public mixed average ( $q, $db null )
$q string

The column name or expression. Make sure you properly quote column names in the expression.

$db yii\db\Connection

The database connection used to generate the SQL statement. If this parameter is not given, the db application component will be used.

return mixed

The average of the specified column values.

batch() public method

Starts a batch query.

A batch query supports fetching data in batches, which can keep the memory usage under a limit. This method will return a yii\db\BatchQueryResult object which implements the Iterator interface and can be traversed to retrieve the data in batches.

For example,

$query = (new Query)->from('user');
foreach ($query->batch() as $rows) {
    // $rows is an array of 100 or fewer rows from user table
}
public yii\db\BatchQueryResult batch ( $batchSize 100, $db null )
$batchSize integer

The number of records to be fetched in each batch.

$db yii\db\Connection

The database connection. If not set, the "db" application component will be used.

return yii\db\BatchQueryResult

The batch query result. It implements the Iterator interface and can be traversed to retrieve the data in batches.

column() public method

Executes the query and returns the first column of the result.

public array column ( $db null )
$db yii\db\Connection

The database connection used to generate the SQL statement. If this parameter is not given, the db application component will be used.

return array

The first column of the query result. An empty array is returned if the query results in nothing.

count() public method

Returns the number of records.

public integer|string count ( $q '*', $db null )
$q string

The COUNT expression. Defaults to '*'. Make sure you properly quote column names in the expression.

$db yii\db\Connection

The database connection used to generate the SQL statement. If this parameter is not given (or null), the db application component will be used.

return integer|string

Number of records. The result may be a string depending on the underlying database engine and to support integer values higher than a 32bit PHP integer can handle.

create() public static method

Creates a new Query object and copies its property values from an existing one.

The properties being copies are the ones to be used by query builders.

public static yii\db\Query create ( $from )
$from yii\db\Query

The source query object

return yii\db\Query

The new Query object

createCommand() public method

Creates a DB command that can be used to execute this query.

public yii\db\Command createCommand ( $db null )
$db yii\db\Connection

The database connection used to generate the SQL statement. If this parameter is not given, the db application component will be used.

return yii\db\Command

The created DB command instance.

distinct() public method

Sets the value indicating whether to SELECT DISTINCT or not.

public $this distinct ( $value true )
$value boolean

Whether to SELECT DISTINCT or not.

return $this

The query object itself

each() public method

Starts a batch query and retrieves data row by row.

This method is similar to batch() except that in each iteration of the result, only one row of data is returned. For example,

$query = (new Query)->from('user');
foreach ($query->each() as $row) {
}
public yii\db\BatchQueryResult each ( $batchSize 100, $db null )
$batchSize integer

The number of records to be fetched in each batch.

$db yii\db\Connection

The database connection. If not set, the "db" application component will be used.

return yii\db\BatchQueryResult

The batch query result. It implements the Iterator interface and can be traversed to retrieve the data in batches.

exists() public method

Returns a value indicating whether the query result contains any row of data.

public boolean exists ( $db null )
$db yii\db\Connection

The database connection used to generate the SQL statement. If this parameter is not given, the db application component will be used.

return boolean

Whether the query result contains any row of data.

filterHaving() public method (available since version 2.0.11)

Sets the HAVING part of the query but ignores empty operands.

This method is similar to having(). The main difference is that this method will remove empty query operands. As a result, this method is best suited for building query conditions based on filter values entered by users.

The following code shows the difference between this method and having():

// HAVING `age`=:age
$query->filterHaving(['name' => null, 'age' => 20]);
// HAVING `age`=:age
$query->having(['age' => 20]);
// HAVING `name` IS NULL AND `age`=:age
$query->having(['name' => null, 'age' => 20]);

Note that unlike having(), you cannot pass binding parameters to this method.

See also:

public $this filterHaving ( array $condition )
$condition array

The conditions that should be put in the HAVING part. See having() on how to specify this parameter.

return $this

The query object itself

from() public method

Sets the FROM part of the query.

public $this from ( $tables )
$tables string|array

The table(s) to be selected from. This can be either a string (e.g. 'user') or an array (e.g. ['user', 'profile']) specifying one or several table names. Table names can contain schema prefixes (e.g. 'public.user') and/or table aliases (e.g. 'user u'). The method will automatically quote the table names unless it contains some parenthesis (which means the table is given as a sub-query or DB expression).

When the tables are specified as an array, you may also use the array keys as the table aliases (if a table does not need alias, do not use a string key).

Use a Query object to represent a sub-query. In this case, the corresponding array key will be used as the alias for the sub-query.

Here are some examples:

// SELECT * FROM  `user` `u`, `profile`;
$query = (new \yii\db\Query)->from(['u' => 'user', 'profile']);

// SELECT * FROM (SELECT * FROM `user` WHERE `active` = 1) `activeusers`;
$subquery = (new \yii\db\Query)->from('user')->where(['active' => true])
$query = (new \yii\db\Query)->from(['activeusers' => $subquery]);

// subquery can also be a string with plain SQL wrapped in parenthesis
// SELECT * FROM (SELECT * FROM `user` WHERE `active` = 1) `activeusers`;
$subquery = "(SELECT * FROM `user` WHERE `active` = 1)";
$query = (new \yii\db\Query)->from(['activeusers' => $subquery]);
return $this

The query object itself

groupBy() public method

Sets the GROUP BY part of the query.

See also addGroupBy().

public $this groupBy ( $columns )
$columns string|array|yii\db\Expression

The columns to be grouped by. Columns can be specified in either a string (e.g. "id, name") or an array (e.g. ['id', 'name']). The method will automatically quote the column names unless a column contains some parenthesis (which means the column contains a DB expression).

Note that if your group-by is an expression containing commas, you should always use an array to represent the group-by information. Otherwise, the method will not be able to correctly determine the group-by columns.

Since version 2.0.7, an yii\db\Expression object can be passed to specify the GROUP BY part explicitly in plain SQL.

return $this

The query object itself

having() public method

Sets the HAVING part of the query.

See also:

public $this having ( $condition, $params = [] )
$condition string|array|yii\db\Expression

The conditions to be put after HAVING. Please refer to where() on how to specify this parameter.

$params array

The parameters (name => value) to be bound to the query.

return $this

The query object itself

innerJoin() public method

Appends an INNER JOIN part to the query.

public $this innerJoin ( $table, $on '', $params = [] )
$table string|array

The table to be joined.

Use a string to represent the name of the table to be joined. The table name can contain a schema prefix (e.g. 'public.user') and/or table alias (e.g. 'user u'). The method will automatically quote the table name unless it contains some parenthesis (which means the table is given as a sub-query or DB expression).

Use an array to represent joining with a sub-query. The array must contain only one element. The value must be a yii\db\Query object representing the sub-query while the corresponding key represents the alias for the sub-query.

$on string|array

The join condition that should appear in the ON part. Please refer to join() on how to specify this parameter.

$params array

The parameters (name => value) to be bound to the query.

return $this

The query object itself

join() public method

Appends a JOIN part to the query.

The first parameter specifies what type of join it is.

public $this join ( $type, $table, $on '', $params = [] )
$type string

The type of join, such as INNER JOIN, LEFT JOIN.

$table string|array

The table to be joined.

Use a string to represent the name of the table to be joined. The table name can contain a schema prefix (e.g. 'public.user') and/or table alias (e.g. 'user u'). The method will automatically quote the table name unless it contains some parenthesis (which means the table is given as a sub-query or DB expression).

Use an array to represent joining with a sub-query. The array must contain only one element. The value must be a yii\db\Query object representing the sub-query while the corresponding key represents the alias for the sub-query.

$on string|array

The join condition that should appear in the ON part. Please refer to where() on how to specify this parameter.

Note that the array format of where() is designed to match columns to values instead of columns to columns, so the following would not work as expected: ['post.author_id' => 'user.id'], it would match the post.author_id column value against the string 'user.id'. It is recommended to use the string syntax here which is more suited for a join:

'post.author_id = user.id'
$params array

The parameters (name => value) to be bound to the query.

return $this

The query object itself

leftJoin() public method

Appends a LEFT OUTER JOIN part to the query.

public $this leftJoin ( $table, $on '', $params = [] )
$table string|array

The table to be joined.

Use a string to represent the name of the table to be joined. The table name can contain a schema prefix (e.g. 'public.user') and/or table alias (e.g. 'user u'). The method will automatically quote the table name unless it contains some parenthesis (which means the table is given as a sub-query or DB expression).

Use an array to represent joining with a sub-query. The array must contain only one element. The value must be a yii\db\Query object representing the sub-query while the corresponding key represents the alias for the sub-query.

$on string|array

The join condition that should appear in the ON part. Please refer to join() on how to specify this parameter.

$params array

The parameters (name => value) to be bound to the query

return $this

The query object itself

max() public method

Returns the maximum of the specified column values.

public mixed max ( $q, $db null )
$q string

The column name or expression. Make sure you properly quote column names in the expression.

$db yii\db\Connection

The database connection used to generate the SQL statement. If this parameter is not given, the db application component will be used.

return mixed

The maximum of the specified column values.

min() public method

Returns the minimum of the specified column values.

public mixed min ( $q, $db null )
$q string

The column name or expression. Make sure you properly quote column names in the expression.

$db yii\db\Connection

The database connection used to generate the SQL statement. If this parameter is not given, the db application component will be used.

return mixed

The minimum of the specified column values.

one() public method

Executes the query and returns a single row of result.

public array|boolean one ( $db null )
$db yii\db\Connection

The database connection used to generate the SQL statement. If this parameter is not given, the db application component will be used.

return array|boolean

The first row (in terms of an array) of the query result. False is returned if the query results in nothing.

orFilterHaving() public method (available since version 2.0.11)

Adds an additional HAVING condition to the existing one but ignores empty operands.

The new condition and the existing one will be joined using the OR operator.

This method is similar to orHaving(). The main difference is that this method will remove empty query operands. As a result, this method is best suited for building query conditions based on filter values entered by users.

See also:

public $this orFilterHaving ( array $condition )
$condition array

The new HAVING condition. Please refer to having() on how to specify this parameter.

return $this

The query object itself

orHaving() public method

Adds an additional HAVING condition to the existing one.

The new condition and the existing one will be joined using the OR operator.

See also:

public $this orHaving ( $condition, $params = [] )
$condition string|array|yii\db\Expression

The new HAVING condition. Please refer to where() on how to specify this parameter.

$params array

The parameters (name => value) to be bound to the query.

return $this

The query object itself

orWhere() public method

Adds an additional WHERE condition to the existing one.

The new condition and the existing one will be joined using the OR operator.

See also:

public $this orWhere ( $condition, $params = [] )
$condition string|array|yii\db\Expression

The new WHERE condition. Please refer to where() on how to specify this parameter.

$params array

The parameters (name => value) to be bound to the query.

return $this

The query object itself

params() public method

Sets the parameters to be bound to the query.

See also addParams().

public $this params ( $params )
$params array

List of query parameter values indexed by parameter placeholders. For example, [':name' => 'Dan', ':age' => 31].

return $this

The query object itself

populate() public method

Converts the raw query results into the format as specified by this query.

This method is internally used to convert the data fetched from database into the format as required by this query.

public array populate ( $rows )
$rows array

The raw query result from database

return array

The converted query result

prepare() public method

Prepares for building SQL.

This method is called by yii\db\QueryBuilder when it starts to build SQL from a query object. You may override this method to do some final preparation work when converting a query into a SQL statement.

public $this prepare ( $builder )
$builder yii\db\QueryBuilder
return $this

A prepared query instance which will be used by yii\db\QueryBuilder to build the SQL

queryScalar() protected method

Queries a scalar value by setting select() first.

Restores the value of select to make this query reusable.

protected boolean|string queryScalar ( $selectExpression, $db )
$selectExpression string|yii\db\Expression
$db yii\db\Connection|null
rightJoin() public method

Appends a RIGHT OUTER JOIN part to the query.

public $this rightJoin ( $table, $on '', $params = [] )
$table string|array

The table to be joined.

Use a string to represent the name of the table to be joined. The table name can contain a schema prefix (e.g. 'public.user') and/or table alias (e.g. 'user u'). The method will automatically quote the table name unless it contains some parenthesis (which means the table is given as a sub-query or DB expression).

Use an array to represent joining with a sub-query. The array must contain only one element. The value must be a yii\db\Query object representing the sub-query while the corresponding key represents the alias for the sub-query.

$on string|array

The join condition that should appear in the ON part. Please refer to join() on how to specify this parameter.

$params array

The parameters (name => value) to be bound to the query

return $this

The query object itself

scalar() public method

Returns the query result as a scalar value.

The value returned will be the first column in the first row of the query results.

public string|null|false scalar ( $db null )
$db yii\db\Connection

The database connection used to generate the SQL statement. If this parameter is not given, the db application component will be used.

return string|null|false

The value of the first column in the first row of the query result. False is returned if the query result is empty.

select() public method

Sets the SELECT part of the query.

public $this select ( $columns, $option null )
$columns string|array|yii\db\Expression

The columns to be selected. Columns can be specified in either a string (e.g. "id, name") or an array (e.g. ['id', 'name']). Columns can be prefixed with table names (e.g. "user.id") and/or contain column aliases (e.g. "user.id AS user_id"). The method will automatically quote the column names unless a column contains some parenthesis (which means the column contains a DB expression). A DB expression may also be passed in form of an yii\db\Expression object.

Note that if you are selecting an expression like CONCAT(first_name, ' ', last_name), you should use an array to specify the columns. Otherwise, the expression may be incorrectly split into several parts.

When the columns are specified as an array, you may also use array keys as the column aliases (if a column does not need alias, do not use a string key).

Starting from version 2.0.1, you may also select sub-queries as columns by specifying each such column as a Query instance representing the sub-query.

$option string

Additional option that should be appended to the 'SELECT' keyword. For example, in MySQL, the option 'SQL_CALC_FOUND_ROWS' can be used.

return $this

The query object itself

sum() public method

Returns the sum of the specified column values.

public mixed sum ( $q, $db null )
$q string

The column name or expression. Make sure you properly quote column names in the expression.

$db yii\db\Connection

The database connection used to generate the SQL statement. If this parameter is not given, the db application component will be used.

return mixed

The sum of the specified column values.

union() public method

Appends a SQL statement using UNION operator.

public $this union ( $sql, $all false )
$sql string|yii\db\Query

The SQL statement to be appended using UNION

$all boolean

TRUE if using UNION ALL and FALSE if using UNION

return $this

The query object itself

where() public method

Sets the WHERE part of the query.

The method requires a $condition parameter, and optionally a $params parameter specifying the values to be bound to the query.

The $condition parameter should be either a string (e.g. 'id=1') or an array.

The $condition specified as an array can be in one of the following two formats:

  • hash format: ['column1' => value1, 'column2' => value2, ...]
  • operator format: [operator, operand1, operand2, ...]

A condition in hash format represents the following SQL expression in general: column1=value1 AND column2=value2 AND .... In case when a value is an array, an IN expression will be generated. And if a value is null, IS NULL will be used in the generated expression. Below are some examples:

  • ['type' => 1, 'status' => 2] generates (type = 1) AND (status = 2).
  • ['id' => [1, 2, 3], 'status' => 2] generates (id IN (1, 2, 3)) AND (status = 2).
  • ['status' => null] generates status IS NULL.

A condition in operator format generates the SQL expression according to the specified operator, which can be one of the following:

  • and: the operands should be concatenated together using AND. For example, ['and', 'id=1', 'id=2'] will generate id=1 AND id=2. If an operand is an array, it will be converted into a string using the rules described here. For example, ['and', 'type=1', ['or', 'id=1', 'id=2']] will generate type=1 AND (id=1 OR id=2). The method will not do any quoting or escaping.

  • or: similar to the and operator except that the operands are concatenated using OR. For example, ['or', ['type' => [7, 8, 9]], ['id' => [1, 2, 3]]] will generate (type IN (7, 8, 9) OR (id IN (1, 2, 3))).

  • not: this will take only one operand and build the negation of it by prefixing the query string with NOT. For example ['not', ['attribute' => null]] will result in the condition NOT (attribute IS NULL).

  • between: operand 1 should be the column name, and operand 2 and 3 should be the starting and ending values of the range that the column is in. For example, ['between', 'id', 1, 10] will generate id BETWEEN 1 AND 10.

  • not between: similar to between except the BETWEEN is replaced with NOT BETWEEN in the generated condition.

  • in: operand 1 should be a column or DB expression, and operand 2 be an array representing the range of the values that the column or DB expression should be in. For example, ['in', 'id', [1, 2, 3]] will generate id IN (1, 2, 3). The method will properly quote the column name and escape values in the range.

    To create a composite IN condition you can use and array for the column name and value, where the values are indexed by the column name: ['in', ['id', 'name'], [['id' => 1, 'name' => 'foo'], ['id' => 2, 'name' => 'bar']] ].

    You may also specify a sub-query that is used to get the values for the IN-condition: ['in', 'user_id', (new Query())->select('id')->from('users')->where(['active' => 1])]

  • not in: similar to the in operator except that IN is replaced with NOT IN in the generated condition.

  • like: operand 1 should be a column or DB expression, and operand 2 be a string or an array representing the values that the column or DB expression should be like. For example, ['like', 'name', 'tester'] will generate name LIKE '%tester%'. When the value range is given as an array, multiple LIKE predicates will be generated and concatenated using AND. For example, ['like', 'name', ['test', 'sample']] will generate name LIKE '%test%' AND name LIKE '%sample%'. The method will properly quote the column name and escape special characters in the values. Sometimes, you may want to add the percentage characters to the matching value by yourself, you may supply a third operand false to do so. For example, ['like', 'name', '%tester', false] will generate name LIKE '%tester'.

  • or like: similar to the like operator except that OR is used to concatenate the LIKE predicates when operand 2 is an array.

  • not like: similar to the like operator except that LIKE is replaced with NOT LIKE in the generated condition.

  • or not like: similar to the not like operator except that OR is used to concatenate the NOT LIKE predicates.

  • exists: operand 1 is a query object that used to build an EXISTS condition. For example ['exists', (new Query())->select('id')->from('users')->where(['active' => 1])] will result in the following SQL expression: EXISTS (SELECT "id" FROM "users" WHERE "active"=1).

  • not exists: similar to the exists operator except that EXISTS is replaced with NOT EXISTS in the generated condition.

  • Additionally you can specify arbitrary operators as follows: A condition of ['>=', 'id', 10] will result in the following SQL expression: id >= 10.

See also:

public $this where ( $condition, $params = [] )
$condition string|array|yii\db\Expression

The conditions that should be put in the WHERE part.

$params array

The parameters (name => value) to be bound to the query.

return $this

The query object itself