From ac54aa2aee9557746ac902fab156b12b4f84a03c Mon Sep 17 00:00:00 2001 From: "evgen@moonbone.local" <> Date: Wed, 12 Apr 2006 23:05:38 +0400 Subject: [PATCH] Fixed bug#14169: type of group_concat() result changed to blob if tmp_table was used In a simple queries a result of the GROUP_CONCAT() function was always of varchar type. But if length of GROUP_CONCAT() result is greater than 512 chars and temporary table is used during select then the result is converted to blob, due to policy to not to store fields longer than 512 chars in tmp table as varchar fields. In order to provide consistent behaviour, result of GROUP_CONCAT() now will always be converted to blob if it is longer than 512 chars. Item_func_group_concat::field_type() is modified accordingly. --- mysql-test/r/func_gconcat.result | 16 ++++++++++++++++ mysql-test/t/func_gconcat.test | 10 ++++++++++ sql/item_func.cc | 2 +- sql/item_sum.h | 7 +++++++ sql/sql_select.cc | 6 ++++-- sql/unireg.h | 1 + 6 files changed, 39 insertions(+), 3 deletions(-) diff --git a/mysql-test/r/func_gconcat.result b/mysql-test/r/func_gconcat.result index 3cb8da7f63f..ef46d170bda 100644 --- a/mysql-test/r/func_gconcat.result +++ b/mysql-test/r/func_gconcat.result @@ -604,3 +604,19 @@ count(distinct (f1+1)) 1 3 drop table t1; +create table t1 (f1 int unsigned, f2 varchar(255)); +insert into t1 values (1,repeat('a',255)),(2,repeat('b',255)); +select f2,group_concat(f1) from t1 group by f2; +Catalog Database Table Table_alias Column Column_alias Type Length Max length Is_null Flags Decimals Charsetnr +def test t1 t1 f2 f2 253 255 255 Y 0 0 8 +def group_concat(f1) 252 400 1 Y 128 0 63 +f2 group_concat(f1) +aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 1 +bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb 2 +select f2,group_concat(f1) from t1 group by f2 order by 2; +Catalog Database Table Table_alias Column Column_alias Type Length Max length Is_null Flags Decimals Charsetnr +def test t1 t1 f2 f2 253 255 255 Y 0 0 8 +def group_concat(f1) group_concat(f1) 252 400 1 Y 144 0 63 +f2 group_concat(f1) +aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa 1 +bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb 2 diff --git a/mysql-test/t/func_gconcat.test b/mysql-test/t/func_gconcat.test index f116aa6f164..1bb49a312b8 100644 --- a/mysql-test/t/func_gconcat.test +++ b/mysql-test/t/func_gconcat.test @@ -390,4 +390,14 @@ insert into t1 values(1),(2),(3); select f1, group_concat(f1+1) from t1 group by f1 with rollup; select count(distinct (f1+1)) from t1 group by f1 with rollup; drop table t1; + +# +# Bug#14169 type of group_concat() result changed to blob if tmp_table was used +# +create table t1 (f1 int unsigned, f2 varchar(255)); +insert into t1 values (1,repeat('a',255)),(2,repeat('b',255)); +--enable_metadata +select f2,group_concat(f1) from t1 group by f2; +select f2,group_concat(f1) from t1 group by f2 order by 2; +--disable_metadata # End of 4.1 tests diff --git a/sql/item_func.cc b/sql/item_func.cc index d0d2eca7233..174a8c55d01 100644 --- a/sql/item_func.cc +++ b/sql/item_func.cc @@ -307,7 +307,7 @@ Field *Item_func::tmp_table_field(TABLE *t_arg) res= new Field_double(max_length, maybe_null, name, t_arg, decimals); break; case STRING_RESULT: - if (max_length > 255) + if (max_length/collation.collation->mbmaxlen > CONVERT_IF_BIGGER_TO_BLOB) res= new Field_blob(max_length, maybe_null, name, t_arg, collation.collation); else res= new Field_string(max_length, maybe_null, name, t_arg, collation.collation); diff --git a/sql/item_sum.h b/sql/item_sum.h index c972240fcba..0cc2a20faa3 100644 --- a/sql/item_sum.h +++ b/sql/item_sum.h @@ -729,6 +729,13 @@ class Item_func_group_concat : public Item_sum enum Sumfunctype sum_func () const {return GROUP_CONCAT_FUNC;} const char *func_name() const { return "group_concat"; } virtual Item_result result_type () const { return STRING_RESULT; } + enum_field_types field_type() const + { + if (max_length/collation.collation->mbmaxlen > CONVERT_IF_BIGGER_TO_BLOB) + return FIELD_TYPE_BLOB; + else + return MYSQL_TYPE_VAR_STRING; + } void clear(); bool add(); void reset_field(); diff --git a/sql/sql_select.cc b/sql/sql_select.cc index d7aa617cffd..91fc808058f 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -4925,7 +4925,8 @@ static Field* create_tmp_field_from_item(THD *thd, Item *item, TABLE *table, if ((type= item->field_type()) == MYSQL_TYPE_DATETIME || type == MYSQL_TYPE_TIME || type == MYSQL_TYPE_DATE) new_field= item->tmp_table_field_from_field_type(table); - else if (item->max_length/item->collation.collation->mbmaxlen > 255) + else if (item->max_length/item->collation.collation->mbmaxlen > + CONVERT_IF_BIGGER_TO_BLOB) { if (convert_blob_length) new_field= new Field_varstring(convert_blob_length, maybe_null, @@ -5028,7 +5029,8 @@ Field *create_tmp_field(THD *thd, TABLE *table,Item *item, Item::Type type, return new Field_longlong(item_sum->max_length,maybe_null, item->name,table,item->unsigned_flag); case STRING_RESULT: - if (item_sum->max_length > 255) + if (item_sum->max_length/item_sum->collation.collation->mbmaxlen > + CONVERT_IF_BIGGER_TO_BLOB) { if (convert_blob_length) return new Field_varstring(convert_blob_length, maybe_null, diff --git a/sql/unireg.h b/sql/unireg.h index 70df9a89c8f..3fb30315c81 100644 --- a/sql/unireg.h +++ b/sql/unireg.h @@ -60,6 +60,7 @@ #define MAX_MBWIDTH 3 /* Max multibyte sequence */ #define MAX_FIELD_CHARLENGTH 255 +#define CONVERT_IF_BIGGER_TO_BLOB 255 /* Max column width +1 */ #define MAX_FIELD_WIDTH (MAX_FIELD_CHARLENGTH*MAX_MBWIDTH+1)