org.hibernate.dialect
Class SQLServerDialect

java.lang.Object
  org.hibernate.dialect.Dialect
      org.hibernate.dialect.SybaseDialect
          org.hibernate.dialect.SQLServerDialect

public class SQLServerDialect
extends SybaseDialect

A dialect for Microsoft SQL Server 2000 and 2005

Author:

Gavin King

Field Summary

Fields inherited from class org.hibernate.dialect.Dialect

CLOSED_QUOTE, DEFAULT_BATCH_SIZE, NO_BATCH, QUOTE

Constructor Summary

SQLServerDialect()

Method Summary

String	appendIdentitySelectToInsert(String insertSQL) Use insert table(...) values(...) select SCOPE_IDENTITY()
String	appendLockHint(LockMode mode, String tableName) Some dialects support an alternative means to SELECT FOR UPDATE, whereby a "lock hint" is appends to the table name in the from clause.
boolean	areStringComparisonsCaseInsensitive() Are string comparisons implicitly case insensitive.
char	closeQuote() The character specific to this dialect used to close a quoted identifier.
boolean	doesReadCommittedCauseWritersToBlockReaders() For the underlying database, is READ_COMMITTED isolation implemented by forcing readers to wait for write locks to be released?
boolean	doesRepeatableReadCauseReadersToBlockWriters() For the underlying database, is REPEATABLE_READ isolation implemented by forcing writers to wait for read locks to be released?
String	getCurrentTimestampSelectString() Retrieve the command used to retrieve the current timestammp from the database.
String	getLimitString(String querySelect, int offset, int limit) Given a limit and an offset, apply the limit clause to the query.
String	getNoColumnsInsertString() The fragment used to insert a row without specifying any column values.
String	getSelectGUIDString() Get the command used to select a GUID from the underlying database.
char	openQuote() The character specific to this dialect used to begin a quoted identifier.
boolean	supportsCircularCascadeDeleteConstraints() Does this dialect support definition of cascade delete constraints which can cause circular chains?
boolean	supportsLimit() Does this dialect support some form of limiting query results via a SQL clause?
boolean	supportsLimitOffset() Does this dialect's LIMIT support (if any) additionally support specifying an offset?
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	supportsResultSetPositionQueryMethodsOnForwardOnlyCursor() Does this dialect support asking the result set its positioning information on forward only cursors.
boolean	supportsVariableLimit() Does this dialect support bind variables (i.e., prepared statememnt parameters) for its limit/offset?
boolean	useMaxForLimit() Does the LIMIT clause take a "maximum" row number instead of a total number of returned rows? This is easiest understood via an example.

Methods inherited from class org.hibernate.dialect.SybaseDialect

applyLocksToSql, dropTemporaryTableAfterUse, generateTemporaryTableName, getAddColumnString, getForUpdateString, getIdentityColumnString, getIdentitySelectString, getNullColumnString, getResultSet, isCurrentTimestampSelectStringCallable, qualifyIndexName, registerResultSetOutParameter, supportsCurrentTimestampSelection, supportsEmptyInList, supportsExistsInSelect, supportsIdentityColumns, supportsInsertSelectIdentity, supportsTemporaryTables

Methods inherited from class org.hibernate.dialect.Dialect

bindLimitParametersFirst, bindLimitParametersInReverseOrder, buildSQLExceptionConverter, createCaseFragment, createOuterJoinFragment, dropConstraints, forUpdateOfColumns, getAddForeignKeyConstraintString, getAddPrimaryKeyConstraintString, getCascadeConstraintsString, getCastTypeName, getColumnComment, getCreateMultisetTableString, getCreateSequenceString, getCreateSequenceString, getCreateSequenceStrings, getCreateSequenceStrings, getCreateTableString, getCreateTemporaryTablePostfix, getCreateTemporaryTableString, getCurrentTimestampSQLFunctionName, getDefaultProperties, getDialect, getDialect, getDropForeignKeyString, getDropSequenceString, getDropSequenceStrings, getForUpdateNowaitString, getForUpdateNowaitString, getForUpdateString, getForUpdateString, getFunctions, getHibernateTypeName, getHibernateTypeName, getIdentityColumnString, getIdentityInsertString, getIdentitySelectString, getKeywords, getLimitString, getLockingStrategy, getLowercaseFunction, getMaxAliasLength, getNativeIdentifierGeneratorClass, getQuerySequencesString, getSelectClauseNullString, getSelectSequenceNextValString, getSequenceNextValString, getTableComment, getTableTypeString, getTypeName, getTypeName, getViolatedConstraintNameExtracter, hasAlterTable, hasDataTypeInIdentityColumn, hasSelfReferentialForeignKeyBug, performTemporaryTableDDLInIsolation, quote, registerColumnType, registerColumnType, registerFunction, registerHibernateType, registerHibernateType, registerKeyword, supportsBindAsCallableArgument, supportsCascadeDelete, supportsColumnCheck, supportsCommentOn, supportsExpectedLobUsagePattern, supportsIfExistsAfterTableName, supportsIfExistsBeforeTableName, supportsNotNullUnique, supportsOuterJoinForUpdate, supportsParametersInInsertSelect, supportsPooledSequences, supportsRowValueConstructorSyntax, supportsRowValueConstructorSyntaxInInList, supportsSequences, supportsSubqueryOnMutatingTable, supportsSubselectAsInPredicateLHS, supportsTableCheck, supportsUnboundedLobLocatorMaterialization, supportsUnionAll, supportsUnique, supportsUniqueConstraintInCreateAlterTable, toBooleanValueString, toString, transformSelectString, useInputStreamToInsertBlob

Methods inherited from class java.lang.Object

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

Constructor Detail

SQLServerDialect

public SQLServerDialect()

Method Detail

getNoColumnsInsertString

public String getNoColumnsInsertString()

Description copied from class: Dialect

The fragment used to insert a row without specifying any column values. This is not possible on some databases.

Overrides:

getNoColumnsInsertString in class Dialect

Returns:

The appropriate empty values clause.

getLimitString

public String getLimitString(String querySelect,
                             int offset,
                             int limit)

Description copied from class: Dialect

Given a limit and an offset, apply the limit clause to the query.

Overrides:

getLimitString in class Dialect

Parameters:

querySelect - The query to which to apply the limit.

offset - The offset of the limit

limit - The limit of the limit ;)

Returns:

The modified query statement with the limit applied.

appendIdentitySelectToInsert

public String appendIdentitySelectToInsert(String insertSQL)

Use insert table(...) values(...) select SCOPE_IDENTITY()

Overrides:

appendIdentitySelectToInsert in class SybaseDialect

Parameters:

insertSQL - The insert command

Returns:

The insert command with any necessary identity select clause attached.

supportsLimit

public boolean supportsLimit()

Description copied from class: Dialect

Does this dialect support some form of limiting query results via a SQL clause?

Overrides:

supportsLimit in class Dialect

Returns:

True if this dialect supports some form of LIMIT.

useMaxForLimit

public boolean useMaxForLimit()

Description copied from class: Dialect

Does the LIMIT clause take a "maximum" row number instead of a total number of returned rows?

This is easiest understood via an example. Consider you have a table with 20 rows, but you only want to retrieve rows number 11 through 20. Generally, a limit with offset would say that the offset = 11 and the limit = 10 (we only want 10 rows at a time); this is specifying the total number of returned rows. Some dialects require that we instead specify offset = 11 and limit = 20, where 20 is the "last" row we want relative to offset (i.e. total number of rows = 20 - 11 = 9)

So essentially, is limit relative from offset? Or is limit absolute?

Overrides:

useMaxForLimit in class Dialect

Returns:

True if limit is relative from offset; false otherwise.

supportsLimitOffset

public boolean supportsLimitOffset()

Description copied from class: Dialect

Does this dialect's LIMIT support (if any) additionally support specifying an offset?

Overrides:

supportsLimitOffset in class Dialect

Returns:

True if the dialect supports an offset within the limit support.

supportsVariableLimit

public boolean supportsVariableLimit()

Description copied from class: Dialect

Does this dialect support bind variables (i.e., prepared statememnt parameters) for its limit/offset?

Overrides:

supportsVariableLimit in class Dialect

Returns:

True if bind variables can be used; false otherwise.

closeQuote

public char closeQuote()

Description copied from class: Dialect

The character specific to this dialect used to close a quoted identifier.

Overrides:

closeQuote in class Dialect

Returns:

The dialect's specific close quote character.

openQuote

public char openQuote()

Description copied from class: Dialect

The character specific to this dialect used to begin a quoted identifier.

Overrides:

openQuote in class Dialect

Returns:

The dialect's specific open quote character.

appendLockHint

public String appendLockHint(LockMode mode,
                             String tableName)

Description copied from class: Dialect

Some dialects support an alternative means to SELECT FOR UPDATE, whereby a "lock hint" is appends to the table name in the from clause.

contributed by Helge Schulz

Overrides:

appendLockHint in class SybaseDialect

Parameters:

mode - The lock mode to apply

tableName - The name of the table to which to apply the lock hint.

Returns:

The table with any required lock hints.

getSelectGUIDString

public String getSelectGUIDString()

Description copied from class: Dialect

Get the command used to select a GUID from the underlying database.

Optional operation.

Overrides:

getSelectGUIDString in class Dialect

Returns:

The appropriate command.

getCurrentTimestampSelectString

public String getCurrentTimestampSelectString()

Description copied from class: Dialect

Retrieve the command used to retrieve the current timestammp from the database.

Overrides:

getCurrentTimestampSelectString in class SybaseDialect

Returns:

The command.

areStringComparisonsCaseInsensitive

public boolean areStringComparisonsCaseInsensitive()

Description copied from class: Dialect

Are string comparisons implicitly case insensitive.

In other words, does [where 'XYZ' = 'xyz'] resolve to true?

Overrides:

areStringComparisonsCaseInsensitive in class Dialect

Returns:

True if comparisons are case insensitive.

supportsResultSetPositionQueryMethodsOnForwardOnlyCursor

public boolean supportsResultSetPositionQueryMethodsOnForwardOnlyCursor()

Description copied from class: Dialect

Does this dialect support asking the result set its positioning information on forward only cursors. Specifically, in the case of scrolling fetches, Hibernate needs to use ResultSet.isAfterLast() and ResultSet.isBeforeFirst(). Certain drivers do not allow access to these methods for forward only cursors.

NOTE : this is highly driver dependent!

Overrides:

supportsResultSetPositionQueryMethodsOnForwardOnlyCursor in class Dialect

Returns:

True if methods like ResultSet.isAfterLast() and ResultSet.isBeforeFirst() are supported for forward only cursors; false otherwise.

supportsCircularCascadeDeleteConstraints

public boolean supportsCircularCascadeDeleteConstraints()

Description copied from class: Dialect

Does this dialect support definition of cascade delete constraints which can cause circular chains?

Overrides:

supportsCircularCascadeDeleteConstraints in class Dialect

Returns:

True if circular cascade delete constraints are supported; false otherwise.

supportsLobValueChangePropogation

public boolean supportsLobValueChangePropogation()

Description copied from class: Dialect

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...

For BLOBs, the internal value might be changed by: Blob.setBinaryStream(long), Blob.setBytes(long, byte[]), Blob.setBytes(long, byte[], int, int), or Blob.truncate(long).

For CLOBs, the internal value might be changed by: Clob.setAsciiStream(long), Clob.setCharacterStream(long), Clob.setString(long, String), Clob.setString(long, String, int, int), or Clob.truncate(long).

NOTE : I do not know the correct answer currently for databases which (1) are not part of the cruise control process or (2) do not Dialect.supportsExpectedLobUsagePattern().

Overrides:

supportsLobValueChangePropogation in class Dialect

Returns:

True if the changes are propogated back to the database; false otherwise.

doesReadCommittedCauseWritersToBlockReaders

public boolean doesReadCommittedCauseWritersToBlockReaders()

Description copied from class: Dialect

For the underlying database, is READ_COMMITTED isolation implemented by forcing readers to wait for write locks to be released?

Overrides:

doesReadCommittedCauseWritersToBlockReaders in class SybaseDialect

Returns:

True if writers block readers to achieve READ_COMMITTED; false otherwise.

doesRepeatableReadCauseReadersToBlockWriters

public boolean doesRepeatableReadCauseReadersToBlockWriters()

Description copied from class: Dialect

For the underlying database, is REPEATABLE_READ isolation implemented by forcing writers to wait for read locks to be released?

Overrides:

doesRepeatableReadCauseReadersToBlockWriters in class SybaseDialect

Returns:

True if readers block writers to achieve REPEATABLE_READ; false otherwise.