org.apache.calcite.sql2rel.StandardConvertletTable.GreatestConvertlet Class Reference

Inheritance diagram for org.apache.calcite.sql2rel.StandardConvertletTable.GreatestConvertlet:

Collaboration diagram for org.apache.calcite.sql2rel.StandardConvertletTable.GreatestConvertlet:

Public Member Functions
RexNode	convertCall (SqlRexContext cx, SqlCall call)

Detailed Description

Convertlet that converts

GREATEST 

and

LEAST 

.

Definition at line 1333 of file StandardConvertletTable.java.

Member Function Documentation

RexNode org.apache.calcite.sql2rel.StandardConvertletTable.GreatestConvertlet.convertCall ( SqlRexContext  cx, SqlCall  call  )

inline

Definition at line 1334 of file StandardConvertletTable.java.

References run_benchmark_import.type.

                                                               {
      // Translate
      //   GREATEST(a, b, c, d)
      // to
      //   CASE
      //   WHEN a IS NULL OR b IS NULL OR c IS NULL OR d IS NULL
      //   THEN NULL
      //   WHEN a > b AND a > c AND a > d
      //   THEN a
      //   WHEN b > c AND b > d
      //   THEN b
      //   WHEN c > d
      //   THEN c
      //   ELSE d
      //   END
      final RexBuilder rexBuilder = cx.getRexBuilder();
      final RelDataType type = cx.getValidator().getValidatedNodeType(call);
      final SqlBinaryOperator op;
      switch (call.getKind()) {
        case GREATEST:
          op = SqlStdOperatorTable.GREATER_THAN;
          break;
        case LEAST:
          op = SqlStdOperatorTable.LESS_THAN;
          break;
        default:
          throw new AssertionError();
      }
      final List<RexNode> exprs = convertExpressionList(
              cx, call.getOperandList(), SqlOperandTypeChecker.Consistency.NONE);
      final List<RexNode> list = new ArrayList<>();
      final List<RexNode> orList = new ArrayList<>();
      for (RexNode expr : exprs) {
        orList.add(rexBuilder.makeCall(SqlStdOperatorTable.IS_NULL, expr));
      }
      list.add(RexUtil.composeDisjunction(rexBuilder, orList));
      list.add(rexBuilder.makeNullLiteral(type));
      for (int i = 0; i < exprs.size() - 1; i++) {
        RexNode expr = exprs.get(i);
        final List<RexNode> andList = new ArrayList<>();
        for (int j = i + 1; j < exprs.size(); j++) {
          final RexNode expr2 = exprs.get(j);
          andList.add(rexBuilder.makeCall(op, expr, expr2));
        }
        list.add(RexUtil.composeConjunction(rexBuilder, andList));
        list.add(expr);
      }
      list.add(exprs.get(exprs.size() - 1));
      return rexBuilder.makeCall(type, SqlStdOperatorTable.CASE, list);
    }

---

The documentation for this class was generated from the following file:

• /home/jenkins-slave/workspace/core-os-doxygen/java/calcite/src/main/java/org/apache/calcite/sql2rel/StandardConvertletTable.java