Function mysql_sql_parse_field

sqladvisor/main.cc:763–772

}

void mysql_sql_parse_field(Item_field *field,
        Item_func::Functype func_item_type, const char * field_print) {
//    int cardinality = mysql_sql_parse_field_cardinality(field,field_print);
    int cardinality = mysql_sql_parse_field_cardinality_new(field, field_print);
    if (cardinality > CARDINALITY_LEVEL) {
        Field_Description * field_desp = new Field_Description(field,
                cardinality, func_item_type, field_print);
        mysql_sql_parse_index(field_desp);
    }
}

//如果SQL中有group by, 判断group by 的条件是哪一张表的。当group by 来自于多张表,则不做处理。只有当group by 的条件都来自于同一张表,或者这张表是驱动表则将返回这张表,否则返回NULL
TABLE_LIST* mysql_sql_parse_group() {