Commit c882c261 authored by unknown's avatar unknown
Browse files

Bug #6019 - SELECT tries to use too short prefix index on utf8 data 

Field_string::pack should respect max_length as Field_string::pack_key does
parent 28db20e4

mysql-test/r/ctype_utf8.result

+4 −0
Original line number Diff line number Diff line
@@ -798,4 +798,8 @@ insert into t1 values(1,'foo'),(2,'foobar'); 
select * from t1 where b like 'foob%';

a	b

2	foobar

alter table t1 engine=bdb;

select * from t1 where b like 'foob%';

a	b

2	foobar

drop table t1;

mysql-test/t/ctype_utf8.test

+4 −0
Original line number Diff line number Diff line
@@ -643,4 +643,8 @@ create table t1 ( 
--enable_warnings

insert into t1 values(1,'foo'),(2,'foobar');

select * from t1 where b like 'foob%';

--disable_warnings

alter table t1 engine=bdb;

select * from t1 where b like 'foob%';

--enable_warnings

drop table t1;

sql/field.cc

+0 −16
Original line number Diff line number Diff line
@@ -4425,23 +4425,7 @@ void Field_string::sql_type(String &res) const 
  res.length(length);

}





char *Field_string::pack(char *to, const char *from, uint max_length)

{

  const char *end=from+min(field_length,max_length);

  uint length;

  while (end > from && end[-1] == ' ')

    end--;

  length= (end-from);

  *to++= (char) (uchar) length;

  if (field_length > 255)

    *to++= (char) (uchar) (length >> 8);

  memcpy(to, from, (int) length);

  return to+length;

}





char *Field_string::pack_key(char *to, const char *from, uint max_length)

{

  uint length=      min(field_length,max_length);

  uint char_length= max_length/field_charset->mbmaxlen;

sql/field.h

+0 −1
Original line number Diff line number Diff line
@@ -927,7 +927,6 @@ class Field_string :public Field_str { 
  void sort_string(char *buff,uint length);

  void sql_type(String &str) const;

  char *pack(char *to, const char *from, uint max_length=~(uint) 0);

  char *pack_key(char *to, const char *from, uint max_length);

  const char *unpack(char* to, const char *from);

  int pack_cmp(const char *a,const char *b,uint key_length);

  int pack_cmp(const char *b,uint key_length);