diff options
Diffstat (limited to 'sql/item_cmpfunc.cc')
| -rw-r--r-- | sql/item_cmpfunc.cc | 202 |
1 files changed, 120 insertions, 82 deletions
diff --git a/sql/item_cmpfunc.cc b/sql/item_cmpfunc.cc index c29031d25b5..c6b88cd8188 100644 --- a/sql/item_cmpfunc.cc +++ b/sql/item_cmpfunc.cc @@ -636,56 +636,51 @@ int Arg_comparator::set_compare_func(Item_bool_func2 *item, Item_result type) return 0; } - /** - @brief Convert date provided in a string to the int representation. - - @param[in] thd thread handle - @param[in] str a string to convert - @param[in] warn_type type of the timestamp for issuing the warning - @param[in] warn_name field name for issuing the warning - @param[out] error_arg could not extract a DATE or DATETIME - - @details Convert date provided in the string str to the int - representation. If the string contains wrong date or doesn't - contain it at all then a warning is issued. The warn_type and - the warn_name arguments are used as the name and the type of the - field when issuing the warning. If any input was discarded - (trailing or non-timestampy characters), was_cut will be non-zero. - was_type will return the type str_to_datetime() could correctly - extract. - - @return - converted value. 0 on error and on zero-dates -- check 'failure' + Parse date provided in a string to a MYSQL_TIME. + + @param[in] thd Thread handle + @param[in] str A string to convert + @param[in] warn_type Type of the timestamp for issuing the warning + @param[in] warn_name Field name for issuing the warning + @param[out] l_time The MYSQL_TIME objects is initialized. + + Parses a date provided in the string str into a MYSQL_TIME object. If the + string contains an incorrect date or doesn't correspond to a date at all + then a warning is issued. The warn_type and the warn_name arguments are used + as the name and the type of the field when issuing the warning. If any input + was discarded (trailing or non-timestamp-y characters), return value will be + TRUE. + + @return Status flag + @retval FALSE Success. + @retval True Indicates failure. */ -static ulonglong -get_date_from_str(THD *thd, String *str, timestamp_type warn_type, - char *warn_name, bool *error_arg) +bool get_mysql_time_from_str(THD *thd, String *str, timestamp_type warn_type, + const char *warn_name, MYSQL_TIME *l_time) { - ulonglong value= 0; + bool value; int error; - MYSQL_TIME l_time; - enum_mysql_timestamp_type ret; + enum_mysql_timestamp_type timestamp_type; - ret= str_to_datetime(str->ptr(), str->length(), &l_time, - (TIME_FUZZY_DATE | MODE_INVALID_DATES | - (thd->variables.sql_mode & - (MODE_NO_ZERO_IN_DATE | MODE_NO_ZERO_DATE))), - &error); + timestamp_type= + str_to_datetime(str->ptr(), str->length(), l_time, + (TIME_FUZZY_DATE | MODE_INVALID_DATES | + (thd->variables.sql_mode & + (MODE_NO_ZERO_IN_DATE | MODE_NO_ZERO_DATE))), + &error); - if (ret == MYSQL_TIMESTAMP_DATETIME || ret == MYSQL_TIMESTAMP_DATE) - { + if (timestamp_type == MYSQL_TIMESTAMP_DATETIME || + timestamp_type == MYSQL_TIMESTAMP_DATE) /* Do not return yet, we may still want to throw a "trailing garbage" warning. */ - *error_arg= FALSE; - value= TIME_to_ulonglong_datetime(&l_time); - } + value= FALSE; else { - *error_arg= TRUE; + value= TRUE; error= 1; /* force warning */ } @@ -698,6 +693,37 @@ get_date_from_str(THD *thd, String *str, timestamp_type warn_type, } +/** + @brief Convert date provided in a string to the int representation. + + @param[in] thd thread handle + @param[in] str a string to convert + @param[in] warn_type type of the timestamp for issuing the warning + @param[in] warn_name field name for issuing the warning + @param[out] error_arg could not extract a DATE or DATETIME + + @details Convert date provided in the string str to the int + representation. If the string contains wrong date or doesn't + contain it at all then a warning is issued. The warn_type and + the warn_name arguments are used as the name and the type of the + field when issuing the warning. + + @return + converted value. 0 on error and on zero-dates -- check 'failure' +*/ +static ulonglong get_date_from_str(THD *thd, String *str, + timestamp_type warn_type, + const char *warn_name, bool *error_arg) +{ + MYSQL_TIME l_time; + *error_arg= get_mysql_time_from_str(thd, str, warn_type, warn_name, &l_time); + + if (*error_arg) + return 0; + return TIME_to_ulonglong_datetime(&l_time); +} + + /* Check whether compare_datetime() can be used to compare items. @@ -1559,61 +1585,73 @@ longlong Item_in_optimizer::val_int() if (cache->null_value) { + /* + We're evaluating + "<outer_value_list> [NOT] IN (SELECT <inner_value_list>...)" + where one or more of the outer values is NULL. + */ if (((Item_in_subselect*)args[1])->is_top_level_item()) { /* - We're evaluating "NULL IN (SELECT ...)". The result can be NULL or - FALSE, and we can return one instead of another. Just return NULL. + We're evaluating a top level item, e.g. + "<outer_value_list> IN (SELECT <inner_value_list>...)", + and in this case a NULL value in the outer_value_list means + that the result shall be NULL/FALSE (makes no difference for + top level items). The cached value is NULL, so just return + NULL. */ null_value= 1; } else { - if (!((Item_in_subselect*)args[1])->is_correlated && - result_for_null_param != UNKNOWN) + /* + We're evaluating an item where a NULL value in either the + outer or inner value list does not automatically mean that we + can return NULL/FALSE. An example of such a query is + "<outer_value_list> NOT IN (SELECT <inner_value_list>...)" + The result when there is at least one NULL value is: NULL if the + SELECT evaluated over the non-NULL values produces at least + one row, FALSE otherwise + */ + Item_in_subselect *item_subs=(Item_in_subselect*)args[1]; + bool all_left_cols_null= true; + const uint ncols= cache->cols(); + + /* + Turn off the predicates that are based on column compares for + which the left part is currently NULL + */ + for (uint i= 0; i < ncols; i++) { - /* Use cached value from previous execution */ - null_value= result_for_null_param; + if (cache->element_index(i)->null_value) + item_subs->set_cond_guard_var(i, FALSE); + else + all_left_cols_null= false; } - else + + if (!((Item_in_subselect*)args[1])->is_correlated && + all_left_cols_null && result_for_null_param != UNKNOWN) { - /* - We're evaluating "NULL IN (SELECT ...)". The result is: - FALSE if SELECT produces an empty set, or - NULL otherwise. - We disable the predicates we've pushed down into subselect, run the - subselect and see if it has produced any rows. + /* + This is a non-correlated subquery, all values in the outer + value list are NULL, and we have already evaluated the + subquery for all NULL values: Return the same result we + did last time without evaluating the subquery. */ - Item_in_subselect *item_subs=(Item_in_subselect*)args[1]; - if (cache->cols() == 1) - { - item_subs->set_cond_guard_var(0, FALSE); - (void) args[1]->val_bool_result(); - result_for_null_param= null_value= !item_subs->engine->no_rows(); - item_subs->set_cond_guard_var(0, TRUE); - } - else - { - uint i; - uint ncols= cache->cols(); - /* - Turn off the predicates that are based on column compares for - which the left part is currently NULL - */ - for (i= 0; i < ncols; i++) - { - if (cache->element_index(i)->null_value) - item_subs->set_cond_guard_var(i, FALSE); - } - - (void) args[1]->val_bool_result(); - result_for_null_param= null_value= !item_subs->engine->no_rows(); - - /* Turn all predicates back on */ - for (i= 0; i < ncols; i++) - item_subs->set_cond_guard_var(i, TRUE); - } + null_value= result_for_null_param; + } + else + { + /* The subquery has to be evaluated */ + (void) args[1]->val_bool_result(); + null_value= !item_subs->engine->no_rows(); + if (all_left_cols_null) + result_for_null_param= null_value; } + + /* Turn all predicates back on */ + for (uint i= 0; i < ncols; i++) + item_subs->set_cond_guard_var(i, TRUE); } return 0; } @@ -2191,7 +2229,7 @@ uint Item_func_ifnull::decimal_precision() const int arg1_int_part= args[1]->decimal_int_part(); int max_int_part= max(arg0_int_part, arg1_int_part); int precision= max_int_part + decimals; - return precision; + return min(precision, DECIMAL_MAX_PRECISION); } @@ -2375,7 +2413,7 @@ uint Item_func_if::decimal_precision() const int arg1_prec= args[1]->decimal_int_part(); int arg2_prec= args[2]->decimal_int_part(); int precision=max(arg1_prec,arg2_prec) + decimals; - return precision; + return min(precision, DECIMAL_MAX_PRECISION); } @@ -2783,7 +2821,7 @@ uint Item_func_case::decimal_precision() const if (else_expr_num != -1) set_if_bigger(max_int_part, args[else_expr_num]->decimal_int_part()); - return max_int_part + decimals; + return min(max_int_part + decimals, DECIMAL_MAX_PRECISION); } |