diff options
Diffstat (limited to 'sql/item.cc')
| -rw-r--r-- | sql/item.cc | 77 |
1 files changed, 43 insertions, 34 deletions
diff --git a/sql/item.cc b/sql/item.cc index 4c2582e2c5c..263915644df 100644 --- a/sql/item.cc +++ b/sql/item.cc @@ -1608,42 +1608,11 @@ bool agg_item_collations_for_comparison(DTCollation &c, const char *fname, } -/* - Collect arguments' character sets together. - We allow to apply automatic character set conversion in some cases. - The conditions when conversion is possible are: - - arguments A and B have different charsets - - A wins according to coercibility rules - (i.e. a column is stronger than a string constant, - an explicit COLLATE clause is stronger than a column) - - character set of A is either superset for character set of B, - or B is a string constant which can be converted into the - character set of A without data loss. - - If all of the above is true, then it's possible to convert - B into the character set of A, and then compare according - to the collation of A. - - For functions with more than two arguments: - - collect(A,B,C) ::= collect(collect(A,B),C) - - Since this function calls THD::change_item_tree() on the passed Item ** - pointers, it is necessary to pass the original Item **'s, not copies. - Otherwise their values will not be properly restored (see BUG#20769). - If the items are not consecutive (eg. args[2] and args[5]), use the - item_sep argument, ie. - - agg_item_charsets(coll, fname, &args[2], 2, flags, 3) -*/ - -bool agg_item_charsets(DTCollation &coll, const char *fname, - Item **args, uint nargs, uint flags, int item_sep) +bool agg_item_set_converter(DTCollation &coll, const char *fname, + Item **args, uint nargs, uint flags, int item_sep) { Item **arg, *safe_args[2]; - if (agg_item_collations(coll, fname, args, nargs, flags, item_sep)) - return TRUE; /* For better error reporting: save the first and the second argument. @@ -1724,6 +1693,46 @@ bool agg_item_charsets(DTCollation &coll, const char *fname, } +/* + Collect arguments' character sets together. + We allow to apply automatic character set conversion in some cases. + The conditions when conversion is possible are: + - arguments A and B have different charsets + - A wins according to coercibility rules + (i.e. a column is stronger than a string constant, + an explicit COLLATE clause is stronger than a column) + - character set of A is either superset for character set of B, + or B is a string constant which can be converted into the + character set of A without data loss. + + If all of the above is true, then it's possible to convert + B into the character set of A, and then compare according + to the collation of A. + + For functions with more than two arguments: + + collect(A,B,C) ::= collect(collect(A,B),C) + + Since this function calls THD::change_item_tree() on the passed Item ** + pointers, it is necessary to pass the original Item **'s, not copies. + Otherwise their values will not be properly restored (see BUG#20769). + If the items are not consecutive (eg. args[2] and args[5]), use the + item_sep argument, ie. + + agg_item_charsets(coll, fname, &args[2], 2, flags, 3) + +*/ + +bool agg_item_charsets(DTCollation &coll, const char *fname, + Item **args, uint nargs, uint flags, int item_sep) +{ + if (agg_item_collations(coll, fname, args, nargs, flags, item_sep)) + return TRUE; + + return agg_item_set_converter(coll, fname, args, nargs, flags, item_sep); +} + + void Item_ident_for_show::make_field(Send_field *tmp_field) { tmp_field->table_name= tmp_field->org_table_name= table_name; @@ -3010,7 +3019,7 @@ bool Item_param::convert_str_value(THD *thd) str_value.set_charset(value.cs_info.final_character_set_of_str_value); /* Here str_value is guaranteed to be in final_character_set_of_str_value */ - max_length= str_value.length(); + max_length= str_value.numchars() * str_value.charset()->mbmaxlen; decimals= 0; /* str_value_ptr is returned from val_str(). It must be not alloced |