Schema

API reference › yii › db › Schema

abstract class	yii\db\Schema
Extends	yii\base\BaseObject
Implements	yii\base\Configurable
Since	2.0
Source	framework/db/Schema.php

5 subclasses

• yii\db\mssql\Schema
• yii\db\mysql\Schema
• yii\db\oci\Schema
• yii\db\pgsql\Schema
• yii\db\sqlite\Schema

Schema is the base class for concrete DBMS-specific schema classes.

Schema represents the database schema information that is DBMS specific.

Properties

Property	Type	Description	Defined by
$columnSchemaClass	class-string<yii\db\T>|array{class?: class-string<yii\db\T>, __class?: class-string<yii\db\T>}	Column schema class or class config Default: 'yii\db\ColumnSchema'. Available since 2.0.11.	Schema
$db	Connection	The database connection Default: null.	Schema
$defaultSchema	string	The default schema name used for the current session. Default: null.	Schema
$exceptionMap	array	Map of DB errors and corresponding exceptions If left part is found in DB error message exception class from the right part is used. Default: ['SQLSTATE[23' => 'yii\db\IntegrityException'].	Schema
$lastInsertID read-only	string	The row ID of the last row inserted, or the last value retrieved from the sequence object.	Schema
$queryBuilder read-only	yii\db\TQueryBuilder	The query builder for this connection.	Schema
$schemaNames read-only	string[]	All schema names in the database, except system schemas.	Schema
$serverVersion read-only	string	Server version as a string.	Schema
$systemSchemaNames	list<string>	List of schema names that should be excluded from getSchemaNames(). Default: [].	Schema
$tableNames read-only	string[]	All table names in the database.	Schema
$tableSchemas read-only	TableSchema[]	The metadata for all tables in the database.	Schema
$transactionIsolationLevel write-only	string	The transaction isolation level to use for this transaction.	Schema
$columnQuoteCharacter protected	string|string[]	Character used to quote column names. Default: '"'. Available since 2.0.14.	Schema
$tableQuoteCharacter protected	string|string[]	Character used to quote schema, table, etc. names. Default: "'". Available since 2.0.14.	Schema

Methods

Method	Description	Defined by
__construct()	Constructor.	yii\base\BaseObject
__call()	Calls the named method which is not a class method.	yii\base\BaseObject
__get()	Returns the value of an object property.	yii\base\BaseObject
__isset()	Checks if a property is set, i.e. defined and not null.	yii\base\BaseObject
__set()	Sets value of an object property.	yii\base\BaseObject
__unset()	Sets an object property to null.	yii\base\BaseObject
canGetProperty()	Returns a value indicating whether a property can be read.	yii\base\BaseObject
canSetProperty()	Returns a value indicating whether a property can be set.	yii\base\BaseObject
className() static	Returns the fully qualified name of this class.	yii\base\BaseObject
convertException()	Converts a DB exception to a more concrete one if possible.	Schema
createColumnSchemaBuilder()	Create a column schema builder instance giving the type and value precision.	Schema
createQueryBuilder()	Creates a query builder for the database.	Schema
createSavepoint()	Creates a new savepoint.	Schema
findUniqueIndexes()	Returns all unique indexes for the given table.	Schema
getLastInsertID()	Returns the ID of the last inserted row or sequence value.	Schema
getPdoType()	Determines the PDO type for the given PHP data value.	Schema
getQueryBuilder()		Schema
getRawTableName()	Returns the actual name of a given table name.	Schema
getSchemaNames()	Returns all schema names in the database, except system schemas.	Schema
getServerVersion()	Returns a server version as a string comparable by version_compare().	Schema
getTableNames()	Returns all table names in the database.	Schema
getTableSchema()	Obtains the metadata for the named table.	Schema
getTableSchemas()	Returns the metadata for all tables in the database.	Schema
hasMethod()	Returns a value indicating whether a method is defined.	yii\base\BaseObject
hasProperty()	Returns a value indicating whether a property is defined.	yii\base\BaseObject
init()	Initializes the object.	yii\base\BaseObject
insert()	Executes the INSERT command, returning primary key values.	Schema
isReadQuery()	Returns a value indicating whether a SQL statement is for read purpose.	Schema
quoteColumnName()	Quotes a column name for use in a query.	Schema
quoteSimpleColumnName()	Quotes a simple column name for use in a query.	Schema
quoteSimpleTableName()	Quotes a simple table name for use in a query.	Schema
quoteTableName()	Quotes a table name for use in a query.	Schema
quoteValue()	Quotes a string value for use in a query.	Schema
refresh()	Refreshes the schema.	Schema
refreshTableSchema()	Refreshes the particular table schema.	Schema
releaseSavepoint()	Releases an existing savepoint.	Schema
resolveRawTableName()	Resolves the table name and schema name (if any) without loading database metadata.	Schema
rollBackSavepoint()	Rolls back to a previously created savepoint.	Schema
setTransactionIsolationLevel()	Sets the isolation level of the current transaction.	Schema
supportsSavepoint()		Schema
unquoteSimpleColumnName()	Unquotes a simple column name.	Schema
unquoteSimpleTableName()	Unquotes a simple table name.	Schema
createColumnSchema() protected	Creates a column schema for the database.	Schema
findSchemaNames() protected	Returns all schema names in the database, including the default one but not system schemas.	Schema
findTableNames() protected	Returns all table names in the database.	Schema
getCacheKey() protected	Returns the cache key for the specified table name.	Schema
getCacheTag() protected	Returns the cache tag name.	Schema
getColumnPhpType() protected	Extracts the PHP type from abstract DB type.	Schema
getSchemaMetadata() protected	Returns the metadata of the given type for all tables in the given schema.	Schema
getTableMetadata() protected	Returns the metadata of the given type for the given table.	Schema
getTableNameParts() protected	Splits full table name into parts.	Schema
loadTableSchema() protected abstract	Loads the metadata for the specified table.	Schema
normalizePdoRowKeyCase() protected	Changes row’s array key case to lower if PDO’s one is set to uppercase.	Schema
resolveTableName() protected	Resolves the table name and schema name (if any).	Schema
setTableMetadata() protected	Sets the metadata of the given type for the given table.	Schema

Constants

Constant	Value	Description	Defined by
TYPE_PK	'pk'		Schema
TYPE_UPK	'upk'		Schema
TYPE_BIGPK	'bigpk'		Schema
TYPE_UBIGPK	'ubigpk'		Schema
TYPE_CHAR	'char'		Schema
TYPE_STRING	'string'		Schema
TYPE_TEXT	'text'		Schema
TYPE_TINYINT	'tinyint'		Schema
TYPE_SMALLINT	'smallint'		Schema
TYPE_INTEGER	'integer'		Schema
TYPE_BIGINT	'bigint'		Schema
TYPE_FLOAT	'float'		Schema
TYPE_DOUBLE	'double'		Schema
TYPE_DECIMAL	'decimal'		Schema
TYPE_DATETIME	'datetime'		Schema
TYPE_TIMESTAMP	'timestamp'		Schema
TYPE_TIME	'time'		Schema
TYPE_DATE	'date'		Schema
TYPE_BINARY	'binary'		Schema
TYPE_BOOLEAN	'boolean'		Schema
TYPE_MONEY	'money'		Schema
TYPE_JSON	'json'		Schema
SCHEMA_CACHE_VERSION	1	Schema cache version, to detect incompatibilities in cached values when the data format of the cache changes.	Schema

Property details

$systemSchemaNames

public list<string> $systemSchemaNames = []

List of schema names that should be excluded from getSchemaNames().

DBMS-specific implementations may use this list in findSchemaNames().

$tableSchemas

public yii\db\TableSchema[] $tableSchemas

The metadata for all tables in the database.

Each array element is an instance of TableSchema or its child class.

Access

Read-only (virtual property).

$transactionIsolationLevel

public string $transactionIsolationLevel

The transaction isolation level to use for this transaction.

This can be one of Transaction::READ_UNCOMMITTED, Transaction::READ_COMMITTED, Transaction::REPEATABLE_READ and Transaction::SERIALIZABLE but also a string containing DBMS specific syntax to be used after SET TRANSACTION ISOLATION LEVEL.

Access

Write-only (virtual property).

$columnQuoteCharacter

protected string|string[] $columnQuoteCharacter = '"'

Character used to quote column names.

An array of 2 characters can be used in case starting and ending characters are different.

Since

2.0.14

$tableQuoteCharacter

protected string|string[] $tableQuoteCharacter = "'"

Character used to quote schema, table, etc. names.

An array of 2 characters can be used in case starting and ending characters are different.

Since

2.0.14

Method details

convertException()

public function convertException(Exception $e, string $rawSql): yii\db\Exception

Converts a DB exception to a more concrete one if possible.

Parameters

Parameter	Type	Description
$e	Exception
$rawSql	string	SQL that produced exception

Returns

Exception

createColumnSchemaBuilder()

public function createColumnSchemaBuilder(string $type, int|string|array|null $length = null): yii\db\ColumnSchemaBuilder

Create a column schema builder instance giving the type and value precision.

This method may be overridden by child classes to create a DBMS-specific column schema builder.

Parameters

Parameter	Type	Description
$type	string	Type of the column. See ColumnSchemaBuilder::$type.
$length	int|string|array|null	Length or precision of the column. See ColumnSchemaBuilder::$length.

Returns

ColumnSchemaBuilder: Column schema builder instance

Since

2.0.6

createQueryBuilder()

public function createQueryBuilder(): yii\db\TQueryBuilder

Creates a query builder for the database.

This method may be overridden by child classes to create a DBMS-specific query builder.

Returns

yii\db\TQueryBuilder: Query builder instance

createSavepoint()

public function createSavepoint(string $name): mixed

Creates a new savepoint.

Parameters

Parameter	Type	Description
$name	string	The savepoint name

Returns

mixed

findUniqueIndexes()

public function findUniqueIndexes(yii\db\TableSchema $table): array

Returns all unique indexes for the given table.

Each array element is of the following structure:

[
 'IndexName1' => ['col1' [, ...]],
 'IndexName2' => ['col2' [, ...]],
]

This method should be overridden by child classes in order to support this feature because the default implementation simply throws an exception

Parameters

Parameter	Type	Description
$table	TableSchema	The table metadata

Returns

array: All unique indexes for the given table.

Throws

• yii\base\NotSupportedException: if this method is called

getLastInsertID()

public function getLastInsertID(string $sequenceName = ''): string

Returns the ID of the last inserted row or sequence value.

Parameters

Parameter	Type	Description
$sequenceName	string	Name of the sequence object (required by some DBMS)

Returns

string: The row ID of the last row inserted, or the last value retrieved from the sequence object

Throws

• yii\base\InvalidCallException: if the DB connection is not active

See also

• https://www.php.net/manual/en/function.PDO-lastInsertId.php

getPdoType()

public function getPdoType(mixed $data): int

Determines the PDO type for the given PHP data value.

Parameters

Parameter	Type	Description
$data	mixed	The data whose PDO type is to be determined

Returns

int: The PDO type

See also

• https://www.php.net/manual/en/pdo.constants.php

getQueryBuilder()

public function getQueryBuilder(): yii\db\TQueryBuilder

Returns

yii\db\TQueryBuilder: The query builder for this connection.

getRawTableName()

public function getRawTableName(string $name): string

Returns the actual name of a given table name.

This method will strip off curly brackets from the given table name and replace the percentage character ’%’ with Connection::$tablePrefix.

Parameters

Parameter	Type	Description
$name	string	The table name to be converted

Returns

string: The real name of the given table name

getSchemaNames()

public function getSchemaNames(bool $refresh = false): string[]

Returns all schema names in the database, except system schemas.

Parameters

Parameter	Type	Description
$refresh	bool	Whether to fetch the latest available schema names. If this is false, schema names fetched previously (if available) will be returned.

Returns

string[]: All schema names in the database, except system schemas.

Since

2.0.4

getServerVersion()

public function getServerVersion(): string

Returns a server version as a string comparable by version_compare().

Returns

string: Server version as a string.

Since

2.0.14

getTableNames()

public function getTableNames(string $schema = '', bool $refresh = false): string[]

Returns all table names in the database.

Parameters

Parameter	Type	Description
$schema	string	The schema of the tables. Defaults to empty string, meaning the current or default schema name. If not empty, the returned table names will be prefixed with the schema name.
$refresh	bool	Whether to fetch the latest available table names. If this is false, table names fetched previously (if available) will be returned.

Returns

string[]: All table names in the database.

getTableSchema()

public function getTableSchema(string $name, bool $refresh = false): yii\db\TableSchema|null

Obtains the metadata for the named table.

Parameters

Parameter	Type	Description
$name	string	Table name. The table name may contain schema name if any. Do not quote the table name.
$refresh	bool	Whether to reload the table schema even if it is found in the cache.

Returns

TableSchema|null: Table metadata. null if the named table does not exist.

getTableSchemas()

public function getTableSchemas(string $schema = '', bool $refresh = false): yii\db\TableSchema[]

Returns the metadata for all tables in the database.

Parameters

Parameter	Type	Description
$schema	string	The schema of the tables. Defaults to empty string, meaning the current or default schema name.
$refresh	bool	Whether to fetch the latest available table schemas. If this is false, cached data may be returned if available.

Returns

TableSchema[]: The metadata for all tables in the database. Each array element is an instance of TableSchema or its child class.

insert()

public function insert(string $table, array $columns): array|false

Executes the INSERT command, returning primary key values.

Parameters

Parameter	Type	Description
$table	string	The table that new rows will be inserted into.
$columns	array	The column data (name => value) to be inserted into the table.

Returns

array|false: Primary key values or false if the command fails

Since

2.0.4

isReadQuery()

public function isReadQuery(string $sql): bool

Returns a value indicating whether a SQL statement is for read purpose.

Parameters

Parameter	Type	Description
$sql	string	The SQL statement

Returns

bool: Whether a SQL statement is for read purpose.

quoteColumnName()

public function quoteColumnName(string $name): string

Quotes a column name for use in a query.

If the column name contains prefix, the prefix will also be properly quoted. If the column name is already fully enclosed in the quote characters, or contains ’(’, ’[[’ or ’{{’, then this method will do nothing.

Parameters

Parameter	Type	Description
$name	string	Column name.

Returns

string: The properly quoted column name.

See also

• quoteSimpleColumnName()

quoteSimpleColumnName()

public function quoteSimpleColumnName(string $name): string

Quotes a simple column name for use in a query.

A simple column name should contain the column name only without any prefix. The asterisk character ’*’ and a name already fully enclosed in the quote characters are returned as is; otherwise the name is enclosed and any embedded ending quote character is escaped by doubling it.

Parameters

Parameter	Type	Description
$name	string	Column name.

Returns

string: The properly quoted column name.

quoteSimpleTableName()

public function quoteSimpleTableName(string $name): string

Quotes a simple table name for use in a query.

A simple table name should contain the table name only without any schema prefix. A name already fully enclosed in the quote characters is returned as is; otherwise the name is enclosed and any embedded ending quote character is escaped by doubling it.

Parameters

Parameter	Type	Description
$name	string	Table name.

Returns

string: The properly quoted table name.

quoteTableName()

public function quoteTableName(string $name): string

Quotes a table name for use in a query.

If the table name contains schema prefix, the prefix will also be properly quoted. If the table name is already fully enclosed in the quote characters, or contains ’(’ or ’{{’, then this method will do nothing.

Parameters

Parameter	Type	Description
$name	string	Table name.

Returns

string: The properly quoted table name.

See also

• quoteSimpleTableName()

quoteValue()

public function quoteValue(mixed $str): mixed

Quotes a string value for use in a query.

Note that if the parameter is not a string, it will be returned without change.

Parameters

Parameter	Type	Description
$str	mixed	String to be quoted. If the parameter is not a string, it will be returned without change.

Returns

mixed: The properly quoted string, or the original data if it is not a string.

See also

• https://www.php.net/manual/en/function.PDO-quote.php

refresh()

public function refresh(): mixed

Refreshes the schema.

This method cleans up all cached table schemas so that they can be re-created later to reflect the database schema change.

Returns

mixed

refreshTableSchema()

public function refreshTableSchema(string $name): mixed

Refreshes the particular table schema.

This method cleans up cached table schema so that it can be re-created later to reflect the database schema change.

Parameters

Parameter	Type	Description
$name	string	Table name.

Returns

mixed

Since

2.0.6

releaseSavepoint()

public function releaseSavepoint(string $name): mixed

Releases an existing savepoint.

Parameters

Parameter	Type	Description
$name	string	The savepoint name

Returns

mixed

resolveRawTableName()

public function resolveRawTableName(string $name): yii\db\TableSchema

Resolves the table name and schema name (if any) without loading database metadata.

Parameters

Parameter	Type	Description
$name	string	The table name.

Returns

TableSchema: TableSchema with resolved table, schema, etc. names.

Throws

• yii\base\NotSupportedException: if this method is not supported by the DBMS.

Since

22.0

rollBackSavepoint()

public function rollBackSavepoint(string $name): mixed

Rolls back to a previously created savepoint.

Parameters

Parameter	Type	Description
$name	string	The savepoint name

Returns

mixed

setTransactionIsolationLevel()

public function setTransactionIsolationLevel(string $level): mixed

Sets the isolation level of the current transaction.

Parameters

Parameter	Type	Description
$level	string	The transaction isolation level to use for this transaction. This can be one of Transaction::READ_UNCOMMITTED, Transaction::READ_COMMITTED, Transaction::REPEATABLE_READ and Transaction::SERIALIZABLE but also a string containing DBMS specific syntax to be used after SET TRANSACTION ISOLATION LEVEL.

Returns

mixed

See also

• https://en.wikipedia.org/wiki/Isolation_%28database_systems%29#Isolation_levels

supportsSavepoint()

public function supportsSavepoint(): bool

Returns

bool: Whether this DBMS supports savepoint.

unquoteSimpleColumnName()

public function unquoteSimpleColumnName(string $name): string

Unquotes a simple column name.

A simple column name should contain the column name only without any prefix. Only a name fully enclosed in the quote characters is unquoted: the enclosure is stripped and doubled ending quote characters are collapsed to a single one.

Parameters

Parameter	Type	Description
$name	string	Column name.

Returns

string: Unquoted column name.

Since

2.0.14

unquoteSimpleTableName()

public function unquoteSimpleTableName(string $name): string

Unquotes a simple table name.

A simple table name should contain the table name only without any schema prefix. Only a name fully enclosed in the quote characters is unquoted: the enclosure is stripped and doubled ending quote characters are collapsed to a single one.

Parameters

Parameter	Type	Description
$name	string	Table name.

Returns

string: Unquoted table name.

Since

2.0.14

createColumnSchema()

protected function createColumnSchema(): yii\db\T

Creates a column schema for the database.

This method may be overridden by child classes to create a DBMS-specific column schema.

Returns

yii\db\T: Column schema instance.

Throws

• yii\base\InvalidConfigException: if a column schema class cannot be created.

findSchemaNames()

protected function findSchemaNames(): array

Returns all schema names in the database, including the default one but not system schemas.

This method should be overridden by child classes in order to support this feature because the default implementation simply throws an exception.

Returns

array: All schema names in the database, except system schemas.

Throws

• yii\base\NotSupportedException: if this method is not supported by the DBMS.

Since

2.0.4

findTableNames()

protected function findTableNames(string $schema = ''): array

Returns all table names in the database.

This method should be overridden by child classes in order to support this feature because the default implementation simply throws an exception.

Parameters

Parameter	Type	Description
$schema	string	The schema of the tables. Defaults to empty string, meaning the current or default schema.

Returns

array: All table names in the database. The names have NO schema name prefix.

Throws

• yii\base\NotSupportedException: if this method is not supported by the DBMS.

getCacheKey()

protected function getCacheKey(string $name): mixed

Returns the cache key for the specified table name.

Parameters

Parameter	Type	Description
$name	string	The table name.

Returns

mixed: The cache key.

getCacheTag()

protected function getCacheTag(): string

Returns the cache tag name.

This allows refresh() to invalidate all cached table schemas.

Returns

string: The cache tag name

getColumnPhpType()

protected function getColumnPhpType(yii\db\ColumnSchema $column): string

Extracts the PHP type from abstract DB type.

Parameters

Parameter	Type	Description
$column	ColumnSchema	The column schema information

Returns

string: PHP type name

getSchemaMetadata()

protected function getSchemaMetadata(string $schema, string $type, bool $refresh): array

Returns the metadata of the given type for all tables in the given schema.

This method will call a 'getTable' . ucfirst($type) named method with the table name and the refresh flag to obtain the metadata.

Parameters

Parameter	Type	Description
$schema	string	The schema of the metadata. Defaults to empty string, meaning the current or default schema name.
$type	string	Metadata type.
$refresh	bool	Whether to fetch the latest available table metadata. If this is false, cached data may be returned if available.

Returns

array: Array of metadata.

Since

2.0.13

getTableMetadata()

protected function getTableMetadata(string $name, string $type, bool $refresh): mixed

Returns the metadata of the given type for the given table.

If there’s no metadata in the cache, this method will call a 'loadTable' . ucfirst($type) named method with the table name to obtain the metadata.

Parameters

Parameter	Type	Description
$name	string	Table name. The table name may contain schema name if any. Do not quote the table name.
$type	string	Metadata type.
$refresh	bool	Whether to reload the table metadata even if it is found in the cache.

Returns

mixed: Metadata.

Since

2.0.13

getTableNameParts()

protected function getTableNameParts(string $name): array

Splits full table name into parts.

Parameters

Parameter	Type	Description
$name	string	Full table name.

Returns

array: Table name parts.

Since

2.0.22

loadTableSchema()

abstract protected function loadTableSchema(string $name): yii\db\TableSchema|null

Loads the metadata for the specified table.

Parameters

Parameter	Type	Description
$name	string	Table name

Returns

TableSchema|null: DBMS-dependent table metadata, null if the table does not exist.

normalizePdoRowKeyCase()

protected function normalizePdoRowKeyCase(array $row, bool $multiple): array

Changes row’s array key case to lower if PDO’s one is set to uppercase.

Parameters

Parameter	Type	Description
$row	array	Row’s array or an array of row’s arrays.
$multiple	bool	Whether multiple rows or a single row passed.

Returns

array: Normalized row or rows.

Since

2.0.13

resolveTableName()

protected function resolveTableName(string $name): yii\db\TableSchema

Resolves the table name and schema name (if any).

Parameters

Parameter	Type	Description
$name	string	The table name

Returns

TableSchema: TableSchema with resolved table, schema, etc. names.

Throws

• yii\base\NotSupportedException: if this method is not supported by the DBMS.

Since

2.0.13

setTableMetadata()

protected function setTableMetadata(string $name, string $type, mixed $data): mixed

Sets the metadata of the given type for the given table.

Parameters

Parameter	Type	Description
$name	string	Table name.
$type	string	Metadata type.
$data	mixed	Metadata.

Returns

mixed

Since

2.0.13