Example #1
0
  /**
   * Determines whether a {@link RexCall} requires decimal expansion. It usually requires expansion
   * if it has decimal operands.
   *
   * <p>Exceptions to this rule are:
   *
   * <ul>
   *   <li>isNull doesn't require expansion
   *   <li>It's okay to cast decimals to and from char types
   *   <li>It's okay to cast nulls as decimals
   *   <li>Casts require expansion if their return type is decimal
   *   <li>Reinterpret casts can handle a decimal operand
   * </ul>
   *
   * @param expr expression possibly in need of expansion
   * @param recurse whether to check nested calls
   * @return whether the expression requires expansion
   */
  public static boolean requiresDecimalExpansion(RexNode expr, boolean recurse) {
    if (!(expr instanceof RexCall)) {
      return false;
    }
    RexCall call = (RexCall) expr;

    boolean localCheck = true;
    switch (call.getKind()) {
      case Reinterpret:
      case IsNull:
        localCheck = false;
        break;
      case Cast:
        RelDataType lhsType = call.getType();
        RelDataType rhsType = call.operands[0].getType();
        if (rhsType.getSqlTypeName() == SqlTypeName.NULL) {
          return false;
        }
        if (SqlTypeUtil.inCharFamily(lhsType) || SqlTypeUtil.inCharFamily(rhsType)) {
          localCheck = false;
        } else if (SqlTypeUtil.isDecimal(lhsType) && (lhsType != rhsType)) {
          return true;
        }
        break;
      default:
        localCheck = call.getOperator().requiresDecimalExpansion();
    }

    if (localCheck) {
      if (SqlTypeUtil.isDecimal(call.getType())) {
        // NOTE jvs 27-Mar-2007: Depending on the type factory, the
        // result of a division may be decimal, even though both inputs
        // are integer.
        return true;
      }
      for (int i = 0; i < call.operands.length; i++) {
        if (SqlTypeUtil.isDecimal(call.operands[i].getType())) {
          return true;
        }
      }
    }
    return (recurse && requiresDecimalExpansion(call.operands, recurse));
  }
Example #2
0
 public static void checkCharsetAndCollateConsistentIfCharType(RelDataType type) {
   // (every charset must have a default collation)
   if (SqlTypeUtil.inCharFamily(type)) {
     Charset strCharset = type.getCharset();
     Charset colCharset = type.getCollation().getCharset();
     assert null != strCharset;
     assert null != colCharset;
     if (!strCharset.equals(colCharset)) {
       if (false) {
         // todo: enable this checking when we have a charset to
         //   collation mapping
         throw new Error(
             type.toString()
                 + " was found to have charset '"
                 + strCharset.name()
                 + "' and a mismatched collation charset '"
                 + colCharset.name()
                 + "'");
       }
     }
   }
 }