Package org.hibernate.dialect.sequence

Class TiDBSequenceSupport

java.lang.Object

org.hibernate.dialect.sequence.TiDBSequenceSupport

All Implemented Interfaces:

SequenceSupport

public class TiDBSequenceSupport
extends Object
implements SequenceSupport

Sequence support for TiDBDialect.

Author:

Cong Wang

Field Summary

Fields

Modifier and Type	Field	Description
static final SequenceSupport	INSTANCE

Constructor Summary

Constructors

Constructor	Description
TiDBSequenceSupport()

Method Summary

Modifier and Type	Method	Description
String	getCreateSequenceString(String sequenceName, int initialValue, int incrementSize)	Typically dialects which support sequences can create a sequence with a single command.
String	getDropSequenceString(String sequenceName)	Typically dialects which support sequences can drop a sequence with a single command.
String	getSelectSequenceNextValString(String sequenceName)	Generate the select expression fragment that will retrieve the next value of a sequence as part of another (typically DML) statement.
String	getSelectSequencePreviousValString(String sequenceName)	Generate the select expression fragment that will retrieve the previous value of a sequence as part of another (typically DML) statement.
boolean	sometimesNeedsStartingValue()	Do we need to explicitly specify minvalue or maxvalue when the initial value doesn't have the same sign as the increment?

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.hibernate.dialect.sequence.SequenceSupport

getCreateSequenceString, getCreateSequenceStrings, getDropSequenceStrings, getFromDual, getSequenceNextValString, getSequenceNextValString, getSequencePreviousValString, startingValue, supportsPooledSequences, supportsSequences

Field Details

INSTANCE

public static final SequenceSupport INSTANCE

Constructor Details

TiDBSequenceSupport

public TiDBSequenceSupport()

Method Details

getSelectSequenceNextValString

public String getSelectSequenceNextValString(String sequenceName)

Description copied from interface: SequenceSupport

Generate the select expression fragment that will retrieve the next value of a sequence as part of another (typically DML) statement.

This differs from SequenceSupport.getSequenceNextValString(String) in that it must return an expression usable within another statement.

Specified by:

getSelectSequenceNextValString in interface SequenceSupport

Parameters:

sequenceName - the name of the sequence

Returns:

The "next value" fragment.

getSelectSequencePreviousValString

public String getSelectSequencePreviousValString(String sequenceName)
                                          throws MappingException

Description copied from interface: SequenceSupport

Generate the select expression fragment that will retrieve the previous value of a sequence as part of another (typically DML) statement.

This differs from SequenceSupport.getSequencePreviousValString(String) in that it must return an expression usable within another statement.

Specified by:

getSelectSequencePreviousValString in interface SequenceSupport

Parameters:

sequenceName - the name of the sequence

Returns:

The "previous value" fragment.

Throws:

MappingException - If sequences are not supported.

sometimesNeedsStartingValue

public boolean sometimesNeedsStartingValue()

Description copied from interface: SequenceSupport

Do we need to explicitly specify minvalue or maxvalue when the initial value doesn't have the same sign as the increment?

Specified by:

sometimesNeedsStartingValue in interface SequenceSupport

getCreateSequenceString

public String getCreateSequenceString(String sequenceName,
 int initialValue,
 int incrementSize)
                               throws MappingException

Description copied from interface: SequenceSupport

Typically dialects which support sequences can create a sequence with a single command. This method is a convenience making it easier to implement SequenceSupport.getCreateSequenceStrings(String,int,int) for these dialects.

Overloaded form of SequenceSupport.getCreateSequenceString(String), additionally taking the initial value and increment size to be applied to the sequence definition.

The default definition is to suffix SequenceSupport.getCreateSequenceString(String) with the string: start with initialValue increment by incrementSize for the arguments initialValue and incrementSize. Dialects need to override this method if different key phrases are used to apply the allocation information.

Specified by:

getCreateSequenceString in interface SequenceSupport

Parameters:

sequenceName - The name of the sequence

initialValue - The initial value to apply to 'create sequence' statement

incrementSize - The increment value to apply to 'create sequence' statement

Returns:

The sequence creation command

Throws:

MappingException - If sequences are not supported.

getDropSequenceString

public String getDropSequenceString(String sequenceName)

Description copied from interface: SequenceSupport

Typically dialects which support sequences can drop a sequence with a single command. This is convenience form of SequenceSupport.getDropSequenceStrings(java.lang.String) to help facilitate that.

Dialects which support sequences and can drop a sequence in a single command need *only* override this method. Dialects which support sequences but require multiple commands to drop a sequence should instead override SequenceSupport.getDropSequenceStrings(java.lang.String).

Specified by:

getDropSequenceString in interface SequenceSupport

Parameters:

sequenceName - The name of the sequence

Returns:

The sequence drop commands