org.hibernate.dialect
Class TeradataDialect

java.lang.Object
  org.hibernate.dialect.Dialect
      org.hibernate.dialect.TeradataDialect

public class TeradataDialect
extends Dialect

A dialect for the Teradata database created by MCR as part of the dialect certification process.

Author:

Jay Nance

Field Summary

Fields inherited from class org.hibernate.dialect.Dialect

CLOSED_QUOTE, DEFAULT_BATCH_SIZE, NO_BATCH, QUOTE

Constructor Summary

TeradataDialect()
Constructor

Method Summary

boolean	areStringComparisonsCaseInsensitive() Are string comparisons implicitly case insensitive.
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?
boolean	dropTemporaryTableAfterUse() Do we need to drop the temporary table after use?
String	getAddColumnString() The syntax used to add a column to a table (optional).
String	getCreateMultisetTableString() Slight variation on Dialect.getCreateTableString().
String	getCreateTemporaryTablePostfix() Get any fragments needing to be postfixed to the command for temporary table creation.
String	getCreateTemporaryTableString() Command used to create a temporary table.
String	getForUpdateString() Does this dialect support the FOR UPDATE syntax?
String	getSelectClauseNullString(int sqlType) Given a Types type code, determine an appropriate null value to use in a select clause.
String	getTypeName(int code, int length, int precision, int scale) Get the name of the database type associated with the given java.sql.Types typecode.
Boolean	performTemporaryTableDDLInIsolation() Does the dialect require that temporary table DDL statements occur in isolation from other statements? This would be the case if the creation would cause any current transaction to get committed implicitly.
boolean	supportsBindAsCallableArgument() Does this dialect support using a JDBC bind parameter as an argument to a function or procedure call?
boolean	supportsCascadeDelete()
boolean	supportsCircularCascadeDeleteConstraints() Does this dialect support definition of cascade delete constraints which can cause circular chains?
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	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	supportsSequences() Does this dialect support sequences?
boolean	supportsTemporaryTables() Does this dialect support temporary tables?

Methods inherited from class org.hibernate.dialect.Dialect

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

Methods inherited from class java.lang.Object

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

Constructor Detail

TeradataDialect

public TeradataDialect()

Constructor

Method Detail

getForUpdateString

public String getForUpdateString()

Does this dialect support the FOR UPDATE syntax?

Overrides:

getForUpdateString in class Dialect

Returns:

empty string ... Teradata does not support FOR UPDATE syntax

supportsIdentityColumns

public boolean supportsIdentityColumns()

Description copied from class: Dialect

Does this dialect support identity column key generation?

Overrides:

supportsIdentityColumns in class Dialect

Returns:

True if IDENTITY columns are supported; false otherwise.

supportsSequences

public boolean supportsSequences()

Description copied from class: Dialect

Does this dialect support sequences?

Overrides:

supportsSequences in class Dialect

Returns:

True if sequences supported; false otherwise.

getAddColumnString

public String getAddColumnString()

Description copied from class: Dialect

The syntax used to add a column to a table (optional).

Overrides:

getAddColumnString in class Dialect

Returns:

The "add column" fragment.

supportsTemporaryTables

public boolean supportsTemporaryTables()

Description copied from class: Dialect

Does this dialect support temporary tables?

Overrides:

supportsTemporaryTables in class Dialect

Returns:

True if temp tables are supported; false otherwise.

getCreateTemporaryTableString

public String getCreateTemporaryTableString()

Description copied from class: Dialect

Command used to create a temporary table.

Overrides:

getCreateTemporaryTableString in class Dialect

Returns:

The command used to create a temporary table.

getCreateTemporaryTablePostfix

public String getCreateTemporaryTablePostfix()

Description copied from class: Dialect

Get any fragments needing to be postfixed to the command for temporary table creation.

Overrides:

getCreateTemporaryTablePostfix in class Dialect

Returns:

Any required postfix.

performTemporaryTableDDLInIsolation

public Boolean performTemporaryTableDDLInIsolation()

Description copied from class: Dialect

Does the dialect require that temporary table DDL statements occur in isolation from other statements? This would be the case if the creation would cause any current transaction to get committed implicitly.

JDBC defines a standard way to query for this information via the DatabaseMetaData.dataDefinitionCausesTransactionCommit() method. However, that does not distinguish between temporary table DDL and other forms of DDL; MySQL, for example, reports DDL causing a transaction commit via its driver, even though that is not the case for temporary table DDL.

Possible return values and their meanings:

• Boolean.TRUE - Unequivocally, perform the temporary table DDL in isolation.
• Boolean.FALSE - Unequivocally, do not perform the temporary table DDL in isolation.
• null - defer to the JDBC driver response in regards to DatabaseMetaData.dataDefinitionCausesTransactionCommit()

Overrides:

performTemporaryTableDDLInIsolation in class Dialect

Returns:

see the result matrix above.

dropTemporaryTableAfterUse

public boolean dropTemporaryTableAfterUse()

Description copied from class: Dialect

Do we need to drop the temporary table after use?

Overrides:

dropTemporaryTableAfterUse in class Dialect

Returns:

True if the table should be dropped.

getTypeName

public String getTypeName(int code,
                          int length,
                          int precision,
                          int scale)
                   throws HibernateException

Get the name of the database type associated with the given java.sql.Types typecode.

Overrides:

getTypeName in class Dialect

Parameters:

code - java.sql.Types typecode

length - the length or precision of the column

precision - the precision of the column

scale - the scale of the column

Returns:

the database type name

Throws:

HibernateException

supportsCascadeDelete

public boolean supportsCascadeDelete()

Overrides:

supportsCascadeDelete in class Dialect

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.

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.

supportsEmptyInList

public boolean supportsEmptyInList()

Description copied from class: Dialect

Does this dialect support empty IN lists?

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

Overrides:

supportsEmptyInList in class Dialect

Returns:

True if empty in lists are supported; false otherwise.

getSelectClauseNullString

public String getSelectClauseNullString(int sqlType)

Description copied from class: Dialect

Given a Types type code, determine an appropriate null value to use in a select clause.

One thing to consider here is that certain databases might require proper casting for the nulls here since the select here will be part of a UNION/UNION ALL.

Overrides:

getSelectClauseNullString in class Dialect

Parameters:

sqlType - The Types type code.

Returns:

The appropriate select clause value fragment.

getCreateMultisetTableString

public String getCreateMultisetTableString()

Description copied from class: Dialect

Slight variation on Dialect.getCreateTableString(). Here, we have the command used to create a table when there is no primary key and duplicate rows are expected.

Most databases do not care about the distinction; originally added for Teradata support which does care.

Overrides:

getCreateMultisetTableString in class Dialect

Returns:

The command used to create a multiset table.

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 Dialect

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 Dialect

Returns:

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

supportsBindAsCallableArgument

public boolean supportsBindAsCallableArgument()

Description copied from class: Dialect

Does this dialect support using a JDBC bind parameter as an argument to a function or procedure call?

Overrides:

supportsBindAsCallableArgument in class Dialect

Returns:

True if the database supports accepting bind params as args; false otherwise.