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title: SQLQuery summary: Write and modify direct database queries through SQLQuery.
SQLQuery
A [api:SQLQuery] object represents a SQL query, which can be serialized into a SQL statement. Dealing with low-level
SQL such as mysql_query()
is not encouraged, since the ORM provides powerful abstraction API's.
For example, if you want to run a simple COUNT
SQL statement, the following three statements are functionally
equivalent:
:::php
// Through raw SQL.
$count = DB::query('SELECT COUNT(*) FROM "Member"')->value();
// Through SQLQuery abstraction layer.
$query = new SQLQuery();
$count = $query->setFrom('Member')->setSelect('COUNT(*)')->value();
// Through the ORM.
$count = Member::get()->count();
The SQLQuery object is used by the SilverStripe ORM internally. By understanding SQLQuery, you can modify the SQL that
the ORM creates.
Usage
Select
:::php
$sqlQuery = new SQLQuery();
$sqlQuery->setFrom('Player');
$sqlQuery->selectField('FieldName', 'Name');
$sqlQuery->selectField('YEAR("Birthday")', 'Birthyear');
$sqlQuery->addLeftJoin('Team','"Player"."TeamID" = "Team"."ID"');
$sqlQuery->addWhere('YEAR("Birthday") = 1982');
// $sqlQuery->setOrderBy(...);
// $sqlQuery->setGroupBy(...);
// $sqlQuery->setHaving(...);
// $sqlQuery->setLimit(...);
// $sqlQuery->setDistinct(true);
// Get the raw SQL (optional)
$rawSQL = $sqlQuery->sql();
// Execute and return a Query object
$result = $sqlQuery->execute();
// Iterate over results
foreach($result as $row) {
echo $row['BirthYear'];
}
The $result
is an array lightly wrapped in a database-specific subclass of [api:Query]
. This class implements the
Iterator-interface, and provides convenience-methods for accessing the data.
Delete
:::php
$sqlQuery->setDelete(true);
Insert / Update
Currently not supported through the `SQLQuery` class, please use raw `DB::query()` calls instead.
:::php
DB::query('UPDATE "Player" SET "Status"=\'Active\'');
Joins
:::php
$sqlQuery = new SQLQuery();
$sqlQuery->setFrom('Player');
$sqlQuery->addSelect('COUNT("Player"."ID")');
$sqlQuery->addWhere('"Team"."ID" = 99');
$sqlQuery->addLeftJoin('Team', '"Team"."ID" = "Player"."TeamID"');
$count = $sqlQuery->execute()->value();
Mapping
Creates a map based on the first two columns of the query result.
:::php
$sqlQuery = new SQLQuery();
$sqlQuery->setFrom('Player');
$sqlQuery->setSelect('ID');
$sqlQuery->selectField('CONCAT("Name", ' - ', YEAR("Birthdate")', 'NameWithBirthyear');
$map = $sqlQuery->execute()->map();
echo $map;
// returns array(
// 1 => "Foo - 1920",
// 2 => "Bar - 1936"
// );
Related Documentation
API Documentation
- [api:DataObject]
- [api:SQLQuery]
- [api:DB]
- [api:Query]
- [api:Database]