Commit 60a21d16 authored by unknown's avatar unknown
Browse files

Fix for bug #23254: COMPRESS(NULL) makes all futher COMPRESS() calls on same Item return NULL 

We don't set null_value to 0 in the Item_func_compress::val_str() for 
not-NULL results.


mysql-test/r/func_compress.result:
  Fix for bug #23254: COMPRESS(NULL) makes all futher COMPRESS() calls on same Item return NULL
    - test result.
mysql-test/t/func_compress.test:
  Fix for bug #23254: COMPRESS(NULL) makes all futher COMPRESS() calls on same Item return NULL
    - test case.
sql/item_strfunc.cc:
  Fix for bug #23254: COMPRESS(NULL) makes all futher COMPRESS() calls on same Item return NULL
    - set null_value.
parent e203f0e5

mysql-test/r/func_compress.result

+10 −0
Original line number Diff line number Diff line
@@ -79,3 +79,13 @@ uncompress(a) uncompressed_length(a) 
NULL	NULL

a	1

drop table t1;

create table t1(a blob);

insert into t1 values ('0'), (NULL), ('0');

select compress(a), compress(a) from t1;

select compress(a) is null from t1;

compress(a) is null

0

1

0

drop table t1;

End of 4.1 tests

mysql-test/t/func_compress.test

+13 −1
Original line number Diff line number Diff line
@@ -54,4 +54,16 @@ insert into t1 values(NULL), (compress('a')); 
select uncompress(a), uncompressed_length(a) from t1;

drop table t1;



# End of 4.1 tests
 
#

# Bug #23254: problem with compress(NULL)

#



create table t1(a blob);

insert into t1 values ('0'), (NULL), ('0');

--disable_result_log

select compress(a), compress(a) from t1;

--enable_result_log

select compress(a) is null from t1;

drop table t1;



--echo End of 4.1 tests

sql/item_strfunc.cc

+1 −0
Original line number Diff line number Diff line
@@ -2838,6 +2838,7 @@ String *Item_func_compress::val_str(String *str) 
    null_value= 1;

    return 0;

  }

  null_value= 0;

  if (res->is_empty()) return res;



  /*