Package org.hibernate.dialect.unique

Interface UniqueDelegate

All Known Implementing Classes:

DB2UniqueDelegate, DefaultUniqueDelegate, InformixUniqueDelegate, MySQLUniqueDelegate

public interface UniqueDelegate

Dialect-level delegate in charge of applying "uniqueness" to a column. Uniqueness can be defined in 1 of 3 ways:

1. Add a unique constraint via separate alter table statements. See getAlterTableToAddUniqueKeyCommand(org.hibernate.mapping.UniqueKey, org.hibernate.boot.Metadata). Also, see getAlterTableToDropUniqueKeyCommand(org.hibernate.mapping.UniqueKey, org.hibernate.boot.Metadata)
2. Add a unique constraint via dialect-specific syntax in table create statement. See getTableCreationUniqueConstraintsFragment(org.hibernate.mapping.Table)
3. Add "unique" syntax to the column itself. See getColumnDefinitionUniquenessFragment(org.hibernate.mapping.Column)

#1 & #2 are preferred, if possible; #3 should be solely a fall-back. See HHH-7797.

Method Summary

Modifier and Type	Method	Description
default java.lang.String	getAlterTableToAddUniqueKeyCommand(UniqueKey uniqueKey, Metadata metadata)	Deprecated. Implement getAlterTableToAddUniqueKeyCommand(UniqueKey, Metadata, SqlStringGenerationContext) instead.
default java.lang.String	getAlterTableToAddUniqueKeyCommand(UniqueKey uniqueKey, Metadata metadata, SqlStringGenerationContext context)	Get the SQL ALTER TABLE command to be used to create the given UniqueKey.
default java.lang.String	getAlterTableToDropUniqueKeyCommand(UniqueKey uniqueKey, Metadata metadata)	Deprecated. Implement getAlterTableToDropUniqueKeyCommand(UniqueKey, Metadata, SqlStringGenerationContext) instead.
default java.lang.String	getAlterTableToDropUniqueKeyCommand(UniqueKey uniqueKey, Metadata metadata, SqlStringGenerationContext context)	Get the SQL ALTER TABLE command to be used to drop the given UniqueKey.
default java.lang.String	getColumnDefinitionUniquenessFragment(Column column)	Deprecated. Implement getColumnDefinitionUniquenessFragment(Column, SqlStringGenerationContext) instead.
default java.lang.String	getColumnDefinitionUniquenessFragment(Column column, SqlStringGenerationContext context)	Get the fragment that can be used to make a column unique as part of its column definition.
default java.lang.String	getTableCreationUniqueConstraintsFragment(Table table)	Deprecated. Implement getTableCreationUniqueConstraintsFragment(Table, SqlStringGenerationContext) instead.
default java.lang.String	getTableCreationUniqueConstraintsFragment(Table table, SqlStringGenerationContext context)	Get the fragment that can be used to apply unique constraints as part of table creation.

Method Detail

getColumnDefinitionUniquenessFragment

@Deprecated
default java.lang.String getColumnDefinitionUniquenessFragment(Column column)

Deprecated.

Implement getColumnDefinitionUniquenessFragment(Column, SqlStringGenerationContext) instead.

Get the fragment that can be used to make a column unique as part of its column definition.

This is intended for dialects which do not support unique constraints

Parameters:

column - The column to which to apply the unique

Returns:

The fragment (usually "unique"), empty string indicates the uniqueness will be indicated using a different approach

getColumnDefinitionUniquenessFragment

default java.lang.String getColumnDefinitionUniquenessFragment(Column column,
                                                               SqlStringGenerationContext context)

Get the fragment that can be used to make a column unique as part of its column definition.

This is intended for dialects which do not support unique constraints

Parameters:

column - The column to which to apply the unique

context - A context for SQL string generation

Returns:

The fragment (usually "unique"), empty string indicates the uniqueness will be indicated using a different approach

getTableCreationUniqueConstraintsFragment

@Deprecated
default java.lang.String getTableCreationUniqueConstraintsFragment(Table table)

Deprecated.

Implement getTableCreationUniqueConstraintsFragment(Table, SqlStringGenerationContext) instead.

Get the fragment that can be used to apply unique constraints as part of table creation. The implementation should iterate over the UniqueKey instances for the given table (see Table.getUniqueKeyIterator() and generate the whole fragment for all unique keys

Intended for Dialects which support unique constraint definitions, but just not in separate ALTER statements.

Parameters:

table - The table for which to generate the unique constraints fragment

Returns:

The fragment, typically in the form ", unique(col1, col2), unique( col20)". NOTE: The leading comma is important!

getTableCreationUniqueConstraintsFragment

default java.lang.String getTableCreationUniqueConstraintsFragment(Table table,
                                                                   SqlStringGenerationContext context)

Get the fragment that can be used to apply unique constraints as part of table creation. The implementation should iterate over the UniqueKey instances for the given table (see Table.getUniqueKeyIterator() and generate the whole fragment for all unique keys

Intended for Dialects which support unique constraint definitions, but just not in separate ALTER statements.

Parameters:

table - The table for which to generate the unique constraints fragment

context - A context for SQL string generation

Returns:

The fragment, typically in the form ", unique(col1, col2), unique( col20)". NOTE: The leading comma is important!

getAlterTableToAddUniqueKeyCommand

@Deprecated
default java.lang.String getAlterTableToAddUniqueKeyCommand(UniqueKey uniqueKey,
                                                            Metadata metadata)

Deprecated.

Implement getAlterTableToAddUniqueKeyCommand(UniqueKey, Metadata, SqlStringGenerationContext) instead.

Get the SQL ALTER TABLE command to be used to create the given UniqueKey.

Parameters:

uniqueKey - The UniqueKey instance. Contains all information about the columns

metadata - Access to the bootstrap mapping information

Returns:

The ALTER TABLE command

getAlterTableToAddUniqueKeyCommand

default java.lang.String getAlterTableToAddUniqueKeyCommand(UniqueKey uniqueKey,
                                                            Metadata metadata,
                                                            SqlStringGenerationContext context)

Get the SQL ALTER TABLE command to be used to create the given UniqueKey.

Parameters:

uniqueKey - The UniqueKey instance. Contains all information about the columns

metadata - Access to the bootstrap mapping information

context - A context for SQL string generation

Returns:

The ALTER TABLE command

getAlterTableToDropUniqueKeyCommand

@Deprecated
default java.lang.String getAlterTableToDropUniqueKeyCommand(UniqueKey uniqueKey,
                                                             Metadata metadata)

Deprecated.

Implement getAlterTableToDropUniqueKeyCommand(UniqueKey, Metadata, SqlStringGenerationContext) instead.

Get the SQL ALTER TABLE command to be used to drop the given UniqueKey.

Parameters:

uniqueKey - The UniqueKey instance. Contains all information about the columns

metadata - Access to the bootstrap mapping information

Returns:

The ALTER TABLE command

getAlterTableToDropUniqueKeyCommand

default java.lang.String getAlterTableToDropUniqueKeyCommand(UniqueKey uniqueKey,
                                                             Metadata metadata,
                                                             SqlStringGenerationContext context)

Get the SQL ALTER TABLE command to be used to drop the given UniqueKey.

Parameters:

uniqueKey - The UniqueKey instance. Contains all information about the columns

metadata - Access to the bootstrap mapping information

context - A context for SQL string generation

Returns:

The ALTER TABLE command