Class RDBMSConditionalUpdateAction

java.lang.Object

com.kingsrook.qqq.backend.module.rdbms.actions.AbstractRDBMSAction

com.kingsrook.qqq.backend.module.rdbms.actions.RDBMSConditionalUpdateAction

All Implemented Interfaces:

ConditionalUpdateInterface

public class RDBMSConditionalUpdateAction
extends AbstractRDBMSAction
implements ConditionalUpdateInterface

RDBMS conditional update: one UPDATE t SET ... WHERE <filter> statement, so the compare and the set are atomic in the database. Runs in the caller's transaction when one is given.

Field Summary

Fields inherited from class com.kingsrook.qqq.backend.module.rdbms.actions.AbstractRDBMSAction

actionStrategy, backendMetaData, isCancelled, queryStat, statement

Constructor Summary

Constructors

Constructor	Description
RDBMSConditionalUpdateAction()

Method Summary

Modifier and Type	Method	Description
Instant	databaseNow(QBackendMetaData backend)	The database clock, read with one SELECT.
int	execute(ConditionalUpdateInput input)	Run the update; return the number of rows updated.

Methods inherited from class com.kingsrook.qqq.backend.module.rdbms.actions.AbstractRDBMSAction

bindExpressionTemplate, clonedOrNewFilter, doCancelQuery, doesSelectClauseRequireDistinct, escapeIdentifier, fieldExpression, getActionStrategy, getColumnName, getConnection, getFieldValueFromResultSet, getFieldValueFromResultSet, getQueryStat, getSingleGroupByClause, getTableName, logSQL, makeFieldNameToColumnReferenceFunction, makeFromClause, makeFromClause, makeOrderByClause, makeWhereClause, requireFieldFunctionAdapterNotNull, scrubValue, scrubValue, scrubValue, setBackendMetaData, setLogSQL, setLogSQL, setLogSQLOutput, setLogSQLReformat, setQueryStat, setSqlAndJoinsInQueryStat, setValueIfTableHasField

Methods inherited from class java.lang.Object

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

Constructor Details

RDBMSConditionalUpdateAction

public RDBMSConditionalUpdateAction()

Method Details

execute

public int execute(ConditionalUpdateInput input)
            throws QException

Description copied from interface: ConditionalUpdateInterface

Run the update; return the number of rows updated.

Specified by:

execute in interface ConditionalUpdateInterface

Throws:

QException

databaseNow

public Instant databaseNow(QBackendMetaData backend)
                    throws QException

The database clock, read with one SELECT. Vendors differ in how they hand back the current time, so each is read as UTC explicitly.

Specified by:

databaseNow in interface ConditionalUpdateInterface

Throws:

QException