Package org.h2.expression
Class Operation0
java.lang.Object
org.h2.expression.Expression
org.h2.expression.Operation0
- Direct Known Subclasses:
CurrentDateTimeValueFunction
,CurrentGeneralValueSpecification
,DomainValueExpression
,OnDuplicateKeyValues
,Parameter
,Rownum
,SequenceValue
,SysInfoFunction
,ValueExpression
,Variable
Operation without subexpressions.
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Field Summary
Fields inherited from class org.h2.expression.Expression
AUTO_PARENTHESES, MAP_IN_AGGREGATE, MAP_IN_WINDOW, MAP_INITIAL, WITH_PARENTHESES, WITHOUT_PARENTHESES
Fields inherited from interface org.h2.util.HasSQL
ADD_PLAN_INFORMATION, DEFAULT_SQL_FLAGS, NO_CASTS, QUOTE_ONLY_WHEN_REQUIRED, REPLACE_LOBS_FOR_TRACE, TRACE_SQL_FLAGS
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Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionvoid
mapColumns
(ColumnResolver resolver, int level, int state) Map the columns of the resolver to expression columns.optimize
(SessionLocal session) Try to optimize the expression.void
setEvaluatable
(TableFilter tableFilter, boolean value) Tell the expression columns whether the table filter can return values now.void
updateAggregate
(SessionLocal session, int stage) Update an aggregate value.Methods inherited from class org.h2.expression.Expression
addFilterConditions, createIndexConditions, getAlias, getBooleanValue, getColumnName, getColumnNameForView, getCost, getEnclosedSQL, getNonAliasExpression, getNotIfPossible, getNullable, getSchemaName, getSQL, getSQL, getSQL, getSQL, getSubexpression, getSubexpressionCount, getTableAlias, getTableName, getType, getUnenclosedSQL, getValue, getWhenSQL, getWhenValue, isConstant, isEverything, isIdentity, isNullConstant, isValueSet, isWhenConditionOperand, needParentheses, optimizeCondition, toString, writeExpressions, writeExpressions
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
Methods inherited from interface org.h2.util.HasSQL
getTraceSQL
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Constructor Details
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Operation0
protected Operation0()
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Method Details
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mapColumns
Description copied from class:Expression
Map the columns of the resolver to expression columns.- Specified by:
mapColumns
in classExpression
- Parameters:
resolver
- the column resolverlevel
- the subquery nesting levelstate
- current state for nesting checks, initial value isExpression.MAP_INITIAL
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optimize
Description copied from class:Expression
Try to optimize the expression.- Specified by:
optimize
in classExpression
- Parameters:
session
- the session- Returns:
- the optimized expression
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setEvaluatable
Description copied from class:Expression
Tell the expression columns whether the table filter can return values now. This is used when optimizing the query.- Specified by:
setEvaluatable
in classExpression
- Parameters:
tableFilter
- the table filtervalue
- true if the table filter can return value
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updateAggregate
Description copied from class:Expression
Update an aggregate value. This method is called at statement execution time. It is usually called once for each row, but if the expression is used multiple times (for example in the column list, and as part of the HAVING expression) it is called multiple times - the row counter needs to be used to make sure the internal state is only updated once.- Specified by:
updateAggregate
in classExpression
- Parameters:
session
- the sessionstage
- select stage
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