Beispiel #1
0
  /**
   * Looks up a field with a given name, returning null if not found.
   *
   * @param rowType Row type
   * @param columnName Field name
   * @return Field, or null if not found
   */
  public static RelDataTypeField lookupField(
      boolean caseSensitive, final RelDataType rowType, String columnName) {
    RelDataTypeField field = rowType.getField(columnName, caseSensitive);
    if (field != null) {
      return field;
    }

    // If record type is flagged as having "any field you ask for",
    // return a type. (TODO: Better way to mark accommodating types.)
    RelDataTypeField extra = RelDataTypeImpl.extra(rowType);
    if (extra != null) {
      return new RelDataTypeFieldImpl(columnName, -1, extra.getType());
    }
    return null;
  }
Beispiel #2
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 public static RelDataType createTypeFromProjection(
     RelDataType type,
     List<String> columnNameList,
     RelDataTypeFactory typeFactory,
     boolean caseSensitive) {
   // If the names in columnNameList and type have case-sensitive differences,
   // the resulting type will use those from type. These are presumably more
   // canonical.
   final List<RelDataTypeField> fields = new ArrayList<RelDataTypeField>(columnNameList.size());
   for (String name : columnNameList) {
     RelDataTypeField field = type.getField(name, caseSensitive);
     fields.add(type.getFieldList().get(field.getIndex()));
   }
   return typeFactory.createStructType(fields);
 }
Beispiel #3
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 /**
  * Generates a cast for a row type.
  *
  * @param rexBuilder RexBuilder to use for constructing casts
  * @param lhsRowType target row type
  * @param rhsExps expressions to be cast
  * @return cast expressions
  */
 public static RexNode[] generateCastExpressions(
     RexBuilder rexBuilder, RelDataType lhsRowType, RexNode[] rhsExps) {
   RelDataTypeField[] lhsFields = lhsRowType.getFields();
   final int fieldCount = lhsFields.length;
   RexNode[] castExps = new RexNode[fieldCount];
   assert fieldCount == rhsExps.length;
   for (int i = 0; i < fieldCount; ++i) {
     RelDataTypeField lhsField = lhsFields[i];
     RelDataType lhsType = lhsField.getType();
     RelDataType rhsType = rhsExps[i].getType();
     if (lhsType.equals(rhsType)) {
       castExps[i] = rhsExps[i];
     } else {
       castExps[i] = rexBuilder.makeCast(lhsType, rhsExps[i]);
     }
   }
   return castExps;
 }
Beispiel #4
0
    private List<RelCollation> deduceMonotonicity(SqlValidatorTable table) {
      final RelDataType rowType = table.getRowType();
      final List<RelCollation> collationList = new ArrayList<RelCollation>();

      // Deduce which fields the table is sorted on.
      int i = -1;
      for (RelDataTypeField field : rowType.getFieldList()) {
        ++i;
        final SqlMonotonicity monotonicity = table.getMonotonicity(field.getName());
        if (monotonicity != SqlMonotonicity.NOT_MONOTONIC) {
          final RelFieldCollation.Direction direction =
              monotonicity.isDecreasing()
                  ? RelFieldCollation.Direction.DESCENDING
                  : RelFieldCollation.Direction.ASCENDING;
          collationList.add(
              RelCollationImpl.of(
                  new RelFieldCollation(
                      i, direction, RelFieldCollation.NullDirection.UNSPECIFIED)));
        }
      }
      return collationList;
    }