core/src/main/java/com/orientechnologies/orient/core/sql/parser/OFunctionCall.java
public Iterable<OIdentifiable> executeIndexedFunction(OFromClause target, OCommandContext ctx, OBinaryCompareOperator operator,
      Object rightValue) {
    OSQLFunction function = OSQLEngine.getInstance().getFunction(name.getStringValue());
    if (function instanceof OIndexableSQLFunction) {
      return ((OIndexableSQLFunction) function)
          .searchFromTarget(target, operator, rightValue, ctx, this.getParams().toArray(new OExpression[] {}));
    }
    return null;
  }
public Iterable<OIdentifiable> executeIndexedFunction(OFromClause target, OCommandContext ctx, OBinaryCompareOperator operator,
      Object rightValue) {
    OSQLFunction function = OSQLEngine.getInstance().getFunction(name.getStringValue());
    if (function instanceof OIndexableSQLFunction) {
      return ((OIndexableSQLFunction) function)
          .searchFromTarget(target, operator, rightValue, ctx, this.getParams().toArray(new OExpression[] {}));
    }
    return null;
  }
see OIndexableSQLFunction.searchFromTarget()

@param target
@param ctx
@param operator
@param rightValue

@return