ReduceDecimalsRule.CaseExpander (Apache Calcite API)

java.lang.Object
- org.apache.calcite.rel.rules.ReduceDecimalsRule.RexExpander
- - org.apache.calcite.rel.rules.ReduceDecimalsRule.CaseExpander

Enclosing class:

ReduceDecimalsRule
```
private class ReduceDecimalsRule.CaseExpander
extends ReduceDecimalsRule.RexExpander
```
Expander that rewrites case expressions, in place. Starting from:
```
(when $cond then $val)+ else $default
```
this expander casts all values to the return type. If the target type is a decimal, then the values are then decoded. The result of expansion is that the case operator no longer deals with decimals args. (The return value is encoded if necessary.)
Note: a decimal type is returned iff arguments have decimals.

- Field Summary
  - Fields inherited from class org.apache.calcite.rel.rules.ReduceDecimalsRule.RexExpander
    builder, int8, real8
- Constructor Summary
  
  Constructors
  Modifier Constructor Description
  
  private CaseExpander(RexBuilder rexBuilder)
- Method Summary
  
  All Methods Instance Methods Concrete Methods
  Modifier and Type Method Description
  
  RexNode expand(RexCall call)
  Rewrites an expression containing decimals.
  - Methods inherited from class org.apache.calcite.rel.rules.ReduceDecimalsRule.RexExpander
    accessValue, canExpand, decodeValue, encodeValue, encodeValue, ensureScale, ensureType, ensureType, makeApproxLiteral, makeApproxScaleFactor, makeCase, makeCase, makeDivide, makeExactLiteral, makeIsNegative, makeIsPositive, makeMinus, makeMultiply, makePlus, makeRoundFactor, makeScaleFactor, powerOfTen, scaleDown, scaleDownDouble, scaleUp
  - Methods inherited from class java.lang.Object
    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - CaseExpander
```
private CaseExpander(RexBuilder rexBuilder)
```
- Method Detail
  - expand
```
public RexNode expand(RexCall call)
```
    Description copied from class: ReduceDecimalsRule.RexExpander
    
    Rewrites an expression containing decimals. Normally, this method always performs a rewrite, but implementations may choose to return the original expression if no change was required.
    
    Specified by:
    
    expand in class ReduceDecimalsRule.RexExpander