diff options
Diffstat (limited to 'sql/item_strfunc.cc')
| -rw-r--r-- | sql/item_strfunc.cc | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/sql/item_strfunc.cc b/sql/item_strfunc.cc index ce9897afeed..c7fa049a0d5 100644 --- a/sql/item_strfunc.cc +++ b/sql/item_strfunc.cc @@ -288,11 +288,13 @@ String *Item_func_concat::val_str(String *str) DBUG_ASSERT(fixed == 1); String *res,*res2,*use_as_buff; uint i; + bool is_const= 0; null_value=0; if (!(res=args[0]->val_str(str))) goto null; use_as_buff= &tmp_value; + is_const= args[0]->const_item(); for (i=1 ; i < arg_count ; i++) { if (res->length() == 0) @@ -315,7 +317,7 @@ String *Item_func_concat::val_str(String *str) current_thd->variables.max_allowed_packet); goto null; } - if (res->alloced_length() >= res->length()+res2->length()) + if (!is_const && res->alloced_length() >= res->length()+res2->length()) { // Use old buffer res->append(*res2); } @@ -370,6 +372,7 @@ String *Item_func_concat::val_str(String *str) res= &tmp_value; use_as_buff=str; } + is_const= 0; } } res->set_charset(collation.collation); @@ -389,7 +392,14 @@ void Item_func_concat::fix_length_and_dec() return; for (uint i=0 ; i < arg_count ; i++) - max_result_length+= args[i]->max_length; + { + if (args[i]->collation.collation->mbmaxlen != collation.collation->mbmaxlen) + max_result_length+= (args[i]->max_length / + args[i]->collation.collation->mbmaxlen) * + collation.collation->mbmaxlen; + else + max_result_length+= args[i]->max_length; + } if (max_result_length >= MAX_BLOB_WIDTH) { |