Eliminate PHP notices on sql conversion

[solotandem]

Notice: Undefined offset: 1 in SqlParser->parseSelectFields() (line 1067 of sql_parser/includes/sql_parser.inc).
Notice: Only variable references should be returned by reference in SqlSelect->addField() (line 155 of sql_parser/includes/sql_object.inc).
Notice: Undefined offset: 1 in SqlParser->parseSelectFields() (line 1067 of sql_parser/includes/sql_parser.inc).
Notice: Only variable references should be returned by reference in SqlSelect->addField() (line 155 of sql_parser/includes/sql_object.inc).
Notice: Only variable references should be returned by reference in SqlObject->addTable() (line 50 of sql_parser/includes/sql_object.inc).
Notice: Only variable references should be returned by reference in SqlObject->addTable() (line 50 of sql_parser/includes/sql_object.inc).
Warning: array_shift() expects parameter 1 to be array, null given in SqlDBTNGConverter->convertConditionalFragment() (line 350 of sql_parser/includes/sql_converter.inc).
Warning: array_shift() expects parameter 1 to be array, null given in SqlDBTNGConverter->convertConditionalFragment() (line 350 of sql_parser/includes/sql_converter.inc).
Notice: Undefined property: SqlSelect::$order_by in SqlDBTNGConverter->convertSelect() (line 105 of sql_parser/includes/sql_converter.inc).
Notice: Undefined index: post in sql_parser_parser_form() (line 35 of sql_parser/sql_parser.module).