org.hibernate.dialect

Class HSQLDialect


public class HSQLDialect
extends Dialect

An SQL dialect compatible with HSQLDB (Hypersonic SQL).

Note this version supports HSQLDB version 1.8 and higher, only.

Authors:
Christoph Sturm
Phillip Baird

Nested Class Summary

static class
HSQLDialect.ReadUncommittedLockingStrategy

Field Summary

Fields inherited from class org.hibernate.dialect.Dialect

CLOSED_QUOTE, DEFAULT_BATCH_SIZE, NO_BATCH, QUOTE

Constructor Summary

HSQLDialect()

Method Summary

boolean
bindLimitParametersFirst()
Does the LIMIT clause come at the start of the SELECT statement, rather than at the end?
String
getAddColumnString()
The syntax used to add a column to a table (optional).
protected String
getCreateSequenceString(String sequenceName)
Typically dialects which support sequences can create a sequence with a single command.
protected String
getDropSequenceString(String sequenceName)
Typically dialects which support sequences can drop a sequence with a single command.
String
getForUpdateString()
Get the string to append to SELECT statements to acquire locks for this dialect.
String
getIdentityColumnString()
The syntax used during DDL to define a column as being an IDENTITY.
String
getIdentityInsertString()
The keyword used to insert a generated value into an identity column (or null).
String
getIdentitySelectString()
Get the select command to use to retrieve the last generated IDENTITY value.
String
getLimitString(String sql, boolean hasOffset)
Apply s limit clause to the query.
LockingStrategy
getLockingStrategy(Lockable lockable, LockMode lockMode)
Get a strategy instance which knows how to acquire a database-level lock of the specified mode for this dialect.
String
getQuerySequencesString()
Get the select command used retrieve the names of all sequences.
String
getSelectSequenceNextValString(String sequenceName)
Generate the select expression fragment that will retreive the next value of a sequence as part of another (typically DML) statement.
String
getSequenceNextValString(String sequenceName)
Generate the appropriate select statement to to retreive the next value of a sequence.
ViolatedConstraintNameExtracter
getViolatedConstraintNameExtracter()
boolean
supportsColumnCheck()
Does this dialect support column-level check constraints?
boolean
supportsCurrentTimestampSelection()
Does this dialect support a way to retrieve the database's current timestamp value?
boolean
supportsEmptyInList()
Does this dialect support empty IN lists?

For example, is [where XYZ in ()] a supported construct?

boolean
supportsIdentityColumns()
Does this dialect support identity column key generation?
boolean
supportsIfExistsAfterTableName()
boolean
supportsLimit()
Does this dialect support some form of limiting query results via a SQL clause?
boolean
supportsLobValueChangePropogation()
Does the dialect support propogating changes to LOB values back to the database? Talking about mutating the internal value of the locator as opposed to supplying a new locator instance...
boolean
supportsPooledSequences()
Does this dialect support "pooled" sequences.
boolean
supportsSequences()
Does this dialect support sequences?
boolean
supportsTemporaryTables()
HSQL does not really support temp tables; just take advantage of the fact that it is a single user db...
boolean
supportsUnique()
Does this dialect support the UNIQUE column syntax?

Methods inherited from class org.hibernate.dialect.Dialect

appendIdentitySelectToInsert, appendLockHint, applyLocksToSql, areStringComparisonsCaseInsensitive, bindLimitParametersFirst, bindLimitParametersInReverseOrder, buildSQLExceptionConverter, closeQuote, createCaseFragment, createOuterJoinFragment, doesReadCommittedCauseWritersToBlockReaders, doesRepeatableReadCauseReadersToBlockWriters, dropConstraints, dropTemporaryTableAfterUse, forUpdateOfColumns, generateTemporaryTableName, getAddColumnString, getAddForeignKeyConstraintString, getAddPrimaryKeyConstraintString, getCascadeConstraintsString, getCastTypeName, getColumnComment, getCreateMultisetTableString, getCreateSequenceString, getCreateSequenceString, getCreateSequenceStrings, getCreateSequenceStrings, getCreateTableString, getCreateTemporaryTablePostfix, getCreateTemporaryTableString, getCurrentTimestampSQLFunctionName, getCurrentTimestampSelectString, getDefaultProperties, getDialect, getDialect, getDropForeignKeyString, getDropSequenceString, getDropSequenceStrings, getForUpdateNowaitString, getForUpdateNowaitString, getForUpdateString, getForUpdateString, getForUpdateString, getFunctions, getHibernateTypeName, getHibernateTypeName, getIdentityColumnString, getIdentityColumnString, getIdentityInsertString, getIdentitySelectString, getIdentitySelectString, getKeywords, getLimitString, getLimitString, getLockingStrategy, getLowercaseFunction, getMaxAliasLength, getNativeIdentifierGeneratorClass, getNoColumnsInsertString, getNullColumnString, getQuerySequencesString, getResultSet, getSelectClauseNullString, getSelectGUIDString, getSelectSequenceNextValString, getSequenceNextValString, getTableComment, getTableTypeString, getTypeName, getTypeName, getViolatedConstraintNameExtracter, hasAlterTable, hasDataTypeInIdentityColumn, hasSelfReferentialForeignKeyBug, isCurrentTimestampSelectStringCallable, openQuote, performTemporaryTableDDLInIsolation, qualifyIndexName, quote, registerColumnType, registerColumnType, registerFunction, registerHibernateType, registerHibernateType, registerKeyword, registerResultSetOutParameter, supportsBindAsCallableArgument, supportsCascadeDelete, supportsCircularCascadeDeleteConstraints, supportsColumnCheck, supportsCommentOn, supportsCurrentTimestampSelection, supportsEmptyInList, supportsExistsInSelect, supportsExpectedLobUsagePattern, supportsIdentityColumns, supportsIfExistsAfterTableName, supportsIfExistsBeforeTableName, supportsInsertSelectIdentity, supportsLimit, supportsLimitOffset, supportsLobValueChangePropogation, supportsNotNullUnique, supportsOuterJoinForUpdate, supportsParametersInInsertSelect, supportsPooledSequences, supportsResultSetPositionQueryMethodsOnForwardOnlyCursor, supportsRowValueConstructorSyntax, supportsRowValueConstructorSyntaxInInList, supportsSequences, supportsSubqueryOnMutatingTable, supportsSubselectAsInPredicateLHS, supportsTableCheck, supportsTemporaryTables, supportsUnboundedLobLocatorMaterialization, supportsUnionAll, supportsUnique, supportsUniqueConstraintInCreateAlterTable, supportsVariableLimit, toBooleanValueString, toString, transformSelectString, useInputStreamToInsertBlob, useMaxForLimit

Constructor Details

HSQLDialect

public HSQLDialect()

Method Details

bindLimitParametersFirst

public boolean bindLimitParametersFirst()
Does the LIMIT clause come at the start of the SELECT statement, rather than at the end?
Overrides:
bindLimitParametersFirst in interface Dialect
Returns:
true if limit parameters should come before other parameters

getAddColumnString

public String getAddColumnString()
The syntax used to add a column to a table (optional).
Overrides:
getAddColumnString in interface Dialect
Returns:
The "add column" fragment.

getCreateSequenceString

protected String getCreateSequenceString(String sequenceName)
Typically dialects which support sequences can create a sequence with a single command. This is convenience form of getCreateSequenceStrings to help facilitate that.

Dialects which support sequences and can create a sequence in a single command need *only* override this method. Dialects which support sequences but require multiple commands to create a sequence should instead override getCreateSequenceStrings.

Overrides:
getCreateSequenceString in interface Dialect
Parameters:
sequenceName - The name of the sequence
Returns:
The sequence creation command

getDropSequenceString

protected String getDropSequenceString(String sequenceName)
Typically dialects which support sequences can drop a sequence with a single command. This is convenience form of Dialect.getDropSequenceStrings(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 Dialect.getDropSequenceStrings(String).

Overrides:
getDropSequenceString in interface Dialect
Parameters:
sequenceName - The name of the sequence
Returns:
The sequence drop commands

getForUpdateString

public String getForUpdateString()
Get the string to append to SELECT statements to acquire locks for this dialect.
Overrides:
getForUpdateString in interface Dialect
Returns:
The appropriate FOR UPDATE clause string.

getIdentityColumnString

public String getIdentityColumnString()
The syntax used during DDL to define a column as being an IDENTITY.
Overrides:
getIdentityColumnString in interface Dialect
Returns:
The appropriate DDL fragment.

getIdentityInsertString

public String getIdentityInsertString()
The keyword used to insert a generated value into an identity column (or null). Need if the dialect does not support inserts that specify no column values.
Overrides:
getIdentityInsertString in interface Dialect
Returns:
The appropriate keyword.

getIdentitySelectString

public String getIdentitySelectString()
Get the select command to use to retrieve the last generated IDENTITY value.
Overrides:
getIdentitySelectString in interface Dialect
Returns:
The appropriate select command

getLimitString

public String getLimitString(String sql,
                             boolean hasOffset)
Apply s limit clause to the query.

Typically dialects utilize variable limit caluses when they support limits. Thus, when building the select command we do not actually need to know the limit or the offest since we will just be using placeholders.

Here we do still pass along whether or not an offset was specified so that dialects not supporting offsets can generate proper exceptions. In general, dialects will override one or the other of this method and Dialect.getLimitString(String,int,int).

Overrides:
getLimitString in interface Dialect
Parameters:
hasOffset - Is the query requesting an offset?
Returns:
the modified SQL

getLockingStrategy

public LockingStrategy getLockingStrategy(Lockable lockable,
                                          LockMode lockMode)
Get a strategy instance which knows how to acquire a database-level lock of the specified mode for this dialect.
Overrides:
getLockingStrategy in interface Dialect
Parameters:
lockable - The persister for the entity to be locked.
lockMode - The type of lock to be acquired.
Returns:
The appropriate locking strategy.
Since:
3.2

getQuerySequencesString

public String getQuerySequencesString()
Get the select command used retrieve the names of all sequences.
Overrides:
getQuerySequencesString in interface Dialect
Returns:
The select command; or null if sequences are not supported.
See Also:
SchemaUpdate

getSelectSequenceNextValString

public String getSelectSequenceNextValString(String sequenceName)
Overrides:
getSelectSequenceNextValString in interface Dialect
Parameters:
sequenceName - the name of the sequence
Returns:
The "nextval" fragment.

getSequenceNextValString

public String getSequenceNextValString(String sequenceName)
Generate the appropriate select statement to to retreive the next value of a sequence.

This should be a "stand alone" select statement.

Overrides:
getSequenceNextValString in interface Dialect
Parameters:
sequenceName - the name of the sequence
Returns:
String The "nextval" select string.

getViolatedConstraintNameExtracter

public ViolatedConstraintNameExtracter getViolatedConstraintNameExtracter()
Overrides:
getViolatedConstraintNameExtracter in interface Dialect

supportsColumnCheck

public boolean supportsColumnCheck()
Does this dialect support column-level check constraints?
Overrides:
supportsColumnCheck in interface Dialect
Returns:
True if column-level CHECK constraints are supported; false otherwise.

supportsCurrentTimestampSelection

public boolean supportsCurrentTimestampSelection()
Does this dialect support a way to retrieve the database's current timestamp value?
Overrides:
supportsCurrentTimestampSelection in interface Dialect
Returns:
True if the current timestamp can be retrieved; false otherwise.

supportsEmptyInList

public boolean supportsEmptyInList()
Does this dialect support empty IN lists?

For example, is [where XYZ in ()] a supported construct?

Overrides:
supportsEmptyInList in interface Dialect
Returns:
True if empty in lists are supported; false otherwise.
Since:
3.2

supportsIdentityColumns

public boolean supportsIdentityColumns()
Does this dialect support identity column key generation?
Overrides:
supportsIdentityColumns in interface Dialect
Returns:
True if IDENTITY columns are supported; false otherwise.

supportsIfExistsAfterTableName

public boolean supportsIfExistsAfterTableName()
Overrides:
supportsIfExistsAfterTableName in interface Dialect

supportsLimit

public boolean supportsLimit()
Does this dialect support some form of limiting query results via a SQL clause?
Overrides:
supportsLimit in interface Dialect
Returns:
True if this dialect supports some form of LIMIT.

supportsLobValueChangePropogation

public boolean supportsLobValueChangePropogation()
Overrides:
supportsLobValueChangePropogation in interface Dialect
Returns:
True if the changes are propogated back to the database; false otherwise.
Since:
3.2

supportsPooledSequences

public boolean supportsPooledSequences()
Does this dialect support "pooled" sequences. Not aware of a better name for this. Essentially can we specify the initial and increment values?
Overrides:
supportsPooledSequences in interface Dialect
Returns:
True if such "pooled" sequences are supported; false otherwise.

supportsSequences

public boolean supportsSequences()
Does this dialect support sequences?
Overrides:
supportsSequences in interface Dialect
Returns:
True if sequences supported; false otherwise.

supportsTemporaryTables

public boolean supportsTemporaryTables()
HSQL does not really support temp tables; just take advantage of the fact that it is a single user db...
Overrides:
supportsTemporaryTables in interface Dialect

supportsUnique

public boolean supportsUnique()
Does this dialect support the UNIQUE column syntax?
Overrides:
supportsUnique in interface Dialect
Returns:
boolean