Ejemplo n.º 1
0
 /**
  * Applies a mapping to a field collation.
  *
  * <p>If the field is not mapped, returns null.
  *
  * @param mapping Mapping
  * @param fieldCollation Field collation
  * @return collation with mapping applied
  */
 public static RelFieldCollation apply(
     Mappings.TargetMapping mapping, RelFieldCollation fieldCollation) {
   final int target = mapping.getTargetOpt(fieldCollation.getFieldIndex());
   if (target < 0) {
     return null;
   }
   return fieldCollation.copy(target);
 }
Ejemplo n.º 2
0
 /** Converts a collation to an ORDER BY item. */
 public SqlNode toSql(RelFieldCollation collation) {
   SqlNode node = field(collation.getFieldIndex());
   switch (collation.getDirection()) {
     case DESCENDING:
     case STRICTLY_DESCENDING:
       node = SqlStdOperatorTable.DESC.createCall(POS, node);
   }
   switch (collation.nullDirection) {
     case FIRST:
       node = SqlStdOperatorTable.NULLS_FIRST.createCall(POS, node);
       break;
     case LAST:
       node = SqlStdOperatorTable.NULLS_LAST.createCall(POS, node);
       break;
   }
   return node;
 }