org.apache.beam.sdk.extensions.sql.zetasql

Class SqlNullIfOperatorRewriter

java.lang.Object

org.apache.beam.sdk.extensions.sql.zetasql.SqlNullIfOperatorRewriter

All Implemented Interfaces:

SqlOperatorRewriter

public class SqlNullIfOperatorRewriter
extends java.lang.Object
implements SqlOperatorRewriter

Rewrites NULLIF calls as CASE ($case_no_value) calls.

Turns NULLIF(expression, expression_to_match) into:

CASE
   WHEN expression == expression_to_match THEN NULL
   ELSE expression
   END

Constructor Summary

Constructors

Constructor and Description
SqlNullIfOperatorRewriter()

Method Summary

Modifier and Type	Method and Description
org.apache.calcite.rex.RexNode	apply(org.apache.calcite.rex.RexBuilder rexBuilder, java.util.List<org.apache.calcite.rex.RexNode> operands) Create and return a new RexNode that represents a call to this operator with the specified operands.

Methods inherited from class java.lang.Object

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

Constructor Detail

SqlNullIfOperatorRewriter

public SqlNullIfOperatorRewriter()

Method Detail

apply

public org.apache.calcite.rex.RexNode apply(org.apache.calcite.rex.RexBuilder rexBuilder,
                                            java.util.List<org.apache.calcite.rex.RexNode> operands)

Description copied from interface: SqlOperatorRewriter

Create and return a new RexNode that represents a call to this operator with the specified operands.

Specified by:

apply in interface SqlOperatorRewriter

Parameters:

rexBuilder - A RexBuilder instance to use for creating new RexNodes

operands - The original list of RexNode operands passed to this operator call

Returns:

The created RexNode