Package org.h2.expression

Class ConcatenationOperation

java.lang.Object

org.h2.expression.Expression

org.h2.expression.OperationN

org.h2.expression.ConcatenationOperation

All Implemented Interfaces:

ExpressionWithVariableParameters, HasSQL, Typed

public final class ConcatenationOperation
extends OperationN

Character string concatenation as in 'Hello' || 'World', binary string concatenation as in X'01' || X'AB' or an array concatenation as in ARRAY[1, 2] || 3.

Field Summary

Fields inherited from class org.h2.expression.OperationN

args, argsCount, type

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

Constructor Summary

Constructors

Constructor	Description
ConcatenationOperation()
ConcatenationOperation(Expression op1, Expression op2)

Method Summary

Modifier and Type	Method	Description
private void	determineType(SessionLocal session)
private long	getPrecision(int i)
java.lang.StringBuilder	getUnenclosedSQL(java.lang.StringBuilder builder, int sqlFlags)	Get the SQL statement of this expression.
Value	getValue(SessionLocal session)	Return the resulting value for the current row.
private Value	getValue(SessionLocal session, int l)
private Value	getValue(SessionLocal session, Value l, Value r)
private void	inlineArguments()
private static boolean	isEmpty(Value v)
boolean	needParentheses()	Returns whether this expressions needs to be wrapped in parentheses when it is used as an argument of other expressions.
Expression	optimize(SessionLocal session)	Try to optimize the expression.

Methods inherited from class org.h2.expression.OperationN

addParameter, doneWithParameters, getCost, getSubexpression, getSubexpressionCount, getType, isEverything, mapColumns, optimizeArguments, setEvaluatable, updateAggregate

Methods inherited from class org.h2.expression.Expression

addFilterConditions, createIndexConditions, getAlias, getBooleanValue, getColumnName, getColumnNameForView, getEnclosedSQL, getNonAliasExpression, getNotIfPossible, getNullable, getSchemaName, getSQL, getSQL, getSQL, getSQL, getTableAlias, getTableName, getWhenSQL, getWhenValue, isConstant, isIdentity, isNullConstant, isValueSet, isWhenConditionOperand, 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

Constructor Detail

ConcatenationOperation

public ConcatenationOperation()

ConcatenationOperation

public ConcatenationOperation(Expression op1,
                              Expression op2)

Method Detail

needParentheses

public boolean needParentheses()

Description copied from class: Expression

Returns whether this expressions needs to be wrapped in parentheses when it is used as an argument of other expressions.

Overrides:

needParentheses in class Expression

Returns:

true if it is

getUnenclosedSQL

public java.lang.StringBuilder getUnenclosedSQL(java.lang.StringBuilder builder,
                                                int sqlFlags)

Description copied from class: Expression

Get the SQL statement of this expression. This may not always be the original SQL statement, especially after optimization. Enclosing '(' and ')' are never appended.

Specified by:

getUnenclosedSQL in class Expression

Parameters:

builder - string builder

sqlFlags - formatting flags

Returns:

the specified string builder

getValue

public Value getValue(SessionLocal session)

Description copied from class: Expression

Return the resulting value for the current row.

Specified by:

getValue in class Expression

Parameters:

session - the session

Returns:

the result

getValue

private Value getValue(SessionLocal session,
                       Value l,
                       Value r)

getValue

private Value getValue(SessionLocal session,
                       int l)

optimize

public Expression optimize(SessionLocal session)

Description copied from class: Expression

Try to optimize the expression.

Specified by:

optimize in class Expression

Parameters:

session - the session

Returns:

the optimized expression

determineType

private void determineType(SessionLocal session)

getPrecision

private long getPrecision(int i)

inlineArguments

private void inlineArguments()

isEmpty

private static boolean isEmpty(Value v)