The problem in this bug is when we create temporary tables. When
temporary tables are created for unions, there is some 
inferrence being carried out regarding the type of the column.
Whenever this column type is inferred to be REAL (i.e. FLOAT or
DOUBLE), MySQL will always try to maintain exact precision, and
if that is not possible (there are hardware limits, since FLOAT
and DOUBLE are stored as approximate values) will switch to
using approximate values. The problem here is that at this point
the information about number of significant digits is not 
available. Furthermore, the number of significant digits should
be increased for the AVG function, however, this was not properly 
handled. There are 4 parts to the problem:

#1: DOUBLE and FLOAT fields don't display their proper display 
lengths in max_display_length(). This is hard-coded as 53 for 
DOUBLE and 24 for FLOAT. Now changed to instead return the 
field_length.

#2: Type holders for temporary tables do not preserve the 
max_length of the Item's from which they are created, and is 
instead reverted to the 53 and 24 from above. This causes 
*all* fields to get non-fixed significant digits.

#3: AVG function does not update max_length (display length)
when updating number of decimals.

#4: The function that switches to non-fixed number of 
significant digits should use DBL_DIG + 2 or FLT_DIG + 2 as 
cut-off values (Since fixed precision does not use the 'e' 
notation)

Of these points, #1 is the controversial one, but this 
change is preferred and has been cleared with Monty. The 
function causes quite a few unit tests to blow up and they had
to b changed, but each one is annotated and motivated. We 
frequently see the magical 53 and 24 give way to more relevant
numbers.


mysql-test/r/create.result:
  bug#24791
  
  changed test result
  
  With the changes made for FLOAT and DOUBLE, the original display
  lengths are now preserved.
mysql-test/r/temp_table.result:
  bug#24791
  
  changed test resullt
  
  Test case added
mysql-test/r/type_float.result:
  bug#24791
  
  changed test result
  
  delta 1: field was originally declared as DOUBLE with no display
  length, so the hardware maximum is chosen rather than 53.
  
  delta 2: fields exceed the maximum precision and thus switch to
  non-fixed significant digits
  
  delta 3: Same as above, number of decmals and significant digits
  was not specified when t3 was created.
mysql-test/t/temp_table.test:
  bug#24791
  
  Test case
sql/field.h:
  bug#24791
  
  The method max_display_length is reimplemented as
  
  uint32 max_display_length() { return field_length; }
  
  in Field_double and Field_float. Since all subclasses of 
  Field_real now have the same implementation of this method, the
  implementation has been moved up the hierarchy to Field_real.
sql/item.cc:
  bug#24791
  
  We switch to a non-fixed number of significant digits
  (by setting decimals=NOT_FIXED_DECIMAL) if the calculated 
  display length is greater than the display length of a value 
  with the maximum precision. These values differ for double and 
  float, obviously.
sql/item_sum.cc:
  bug#24791
  
  We must increase the display length accordinly whenever we 
  change number of decimal places.

into  magare.gmz:/home/kgeorge/mysql/autopush/B26794-5.0-opt


sql/field.cc:
  Auto merged

Different set of conditions is used to verify
the validity of index definitions over a GEOMETRY
column in ALTER TABLE and CREATE TABLE. 
The difference was on how sub-keys notion validity
is checked.
Fixed by extending the CREATE TABLE condition to
support the cases allowed in ALTER TABLE.
Made the SHOW CREATE TABLE not to display spatial
indexes using the sub-key notion.


mysql-test/r/alter_table.result:
  Bug #26794: test case
mysql-test/r/gis-rtree.result:
  Bug #26794: fixed SHOW CREATE TABLE output.
mysql-test/t/alter_table.test:
  Bug #26794: test case
sql/field.cc:
  Bug #26794: Allow sub-keys for GEOMETRY
sql/sql_show.cc:
  Bug #26794: Don't show sub-key notion 
   in SHOW CREATE TABLE for SPATIAL indexes.
sql/sql_table.cc:
  Bug #26794: Allow sub-keys for GEOMETRY

into  magare.gmz:/home/kgeorge/mysql/autopush/B26672-5.0-opt


mysql-test/r/order_by.result:
  Auto merged
mysql-test/t/order_by.test:
  Auto merged

into  olga.mysql.com:/home/igor/dev-opt/mysql-5.0-opt-bug26963


mysql-test/r/select.result:
  Auto merged
mysql-test/t/select.test:
  Auto merged

when the column is to be read from a derived table column which 
was specified as a concatenation of string literals.
The bug happened because the Item_string::append did not adjust the
value of Item_string::max_length. As a result of it the temporary 
table column  defined to store the concatenation of literals was 
not wide enough to hold the whole value.



mysql-test/r/subselect.result:
  Added a test case for bug #26738.
mysql-test/t/subselect.test:
  Added a test case for bug #26738.

after single-row table substitution could lead to a wrong result set.
The bug happened because the function Item_field::replace_equal_field
erroniously assumed that any field included in a multiple equality
with a constant has been already substituted for this constant.
This not true for fields becoming constant after row substitutions
for constant tables.
 


mysql-test/r/select.result:
  Added a test case for bug #26963.
mysql-test/t/select.test:
  Added a test case for bug #26963.
sql/item.cc:
  Fixed bug #26963: invalid optimization of the pushdown conditions
  after single-row table substitution could lead to a wrong result set.
  The bug happened because the function Item_field::replace_equal_field
  erroneously assumed that any field included in a multiple equality
  with a constant has been already substituted for this constant.
  This not true for fields becoming constant after row substitutions
  for constant tables.

into  magare.gmz:/home/kgeorge/mysql/autopush/WL3527-5.0-opt-merge

into  moonbone.local:/mnt/gentoo64/work/25373-bug-5.0-opt-mysql


sql/item_strfunc.cc:
  Auto merged
mysql-test/r/func_str.result:
  SCCS merged
mysql-test/t/func_str.test:
  SCCS merged

When the SUBSTRING() function was used over a LONGTEXT field the max_length of
the SUBSTRING() result was wrongly calculated and set to 0. As the max_length
parameter is used while tmp field creation it limits the length of the result
field and leads to printing an empty string instead of the correct result.

Now the Item_func_substr::fix_length_and_dec() function correctly calculates
the max_length parameter.


mysql-test/t/func_str.test:
  Added a test case for the bug#15757: Wrong SUBSTRING() result when a tmp table was employed.
mysql-test/r/func_str.result:
  Added a test case for the bug#15757: Wrong SUBSTRING() result when a tmp table was employed.
sql/item_strfunc.cc:
  Bug#15757: Wrong SUBSTRING() result when a tmp table was employed.
  Now the Item_func_substr::fix_length_and_dec() function correctly calculates
  the max_length parameter.

into  moonbone.local:/mnt/gentoo64/work/25373-bug-5.0-opt-mysql


mysql-test/r/func_str.result:
  Auto merged
mysql-test/r/subselect.result:
  Auto merged
mysql-test/r/union.result:
  Auto merged
sql/item.cc:
  Auto merged

Crash happened because the function get_best_group_min_max detected
joins with ROLLUP incorrectly.


mysql-test/r/olap.result:
  Added a test case for bug #26830.
mysql-test/t/olap.test:
  Added a test case for bug #26830.

away.

Additional fix for bug#22331. Now Item_field prints its value in the case of
the const field.


mysql-test/r/varbinary.result:
  Corrected test case after fix for bug#22331.
mysql-test/r/union.result:
  Corrected test case after fix for bug#22331.
mysql-test/r/subselect.result:
  Corrected test case after fix for bug#22331.
mysql-test/r/func_test.result:
  Corrected test case after fix for bug#22331.
mysql-test/r/having.result:
  Corrected test case after fix for bug#22331.
mysql-test/r/func_regexp.result:
  Corrected test case after fix for bug#22331.
mysql-test/r/func_str.result:
  Corrected test case after fix for bug#22331.
mysql-test/r/func_default.result:
  Corrected test case after fix for bug#22331.
mysql-test/r/explain.result:
  Corrected test case after fix for bug#22331.
sql/sql_union.cc:
  Bug#22331: Wrong WHERE in EXPLAIN EXTENDED when all expressions were optimized
  away.
  Cleanup of the SELECT_LEX::order_list list.
sql/item.h:
  Bug#22331: Wrong WHERE in EXPLAIN EXTENDED when all expressions were optimized
  away.
  Added the print() member function to the Item_field class.
sql/item.cc:
  Bug#22331: Wrong WHERE in EXPLAIN EXTENDED when all expressions were optimized
  away.
  Added the print() member function to the Item_field class.

into  magare.gmz:/home/kgeorge/mysql/work/WL3527-5.0-opt-merge


sql/sql_yacc.yy:
  Auto merged
mysql-test/r/select.result:
  merge
mysql-test/t/select.test:
  merge

         be specified
 5.0 part of the fix. Implements IGNORE INDEX FOR JOIN as a synonym
 of IGNORE INDEX for backward compatibility with the 5.1 fix.


mysql-test/r/select.result:
  WL#3527: Extend IGNORE INDEX so places where index is ignored can 
           be specified
  - test case
mysql-test/t/select.test:
  WL#3527: Extend IGNORE INDEX so places where index is ignored can 
           be specified
  - test case

into  magare.gmz:/home/kgeorge/mysql/autopush/B26281-5.0-opt

into  magare.gmz:/home/kgeorge/mysql/autopush/B26281-5.0-opt


sql/item_strfunc.cc:
  Auto merged
mysql-test/r/func_str.result:
  resolved test merge conflicts
mysql-test/t/func_str.test:
  resolved test merge conflicts

 Fixed boundry checks in the INSERT() function:
 were one off.


mysql-test/r/func_str.result:
  Bug #26281: test case
mysql-test/t/func_str.test:
  Bug #26281: test case
sql/item_strfunc.cc:
  Bug #26281: fixed boundry checks

into  olga.mysql.com:/home/igor/mysql-5.0-opt


sql/item.cc:
  Auto merged

into  olga.mysql.com:/home/igor/dev-opt/mysql-5.0-opt-bug26661

construct references invalid name.
Derived tables currently cannot use outer references.
Thus there is no outer context for them.
The 4.1 code takes this fact into account while the 
Item_field::fix_outer_field code of 5.0 lost the check that blocks
any attempts to resolve names in outer context for derived tables.


mysql-test/r/union.result:
  Added a test case for bug #26661.
mysql-test/t/union.test:
  Added a test case for bug #26661.
sql/item.cc:
  Fixed bug #26661.
  Derived tables currently cannot use outer references.
  Thus there is no outer context for them.
  The 4.1 code takes this fact into account while the 
  Item_field::fix_outer_field code of 5.0 lost the check that blocks
  any attempts to resolve names in outer context for derived tables.

into  mysql.com:/home/hf/work/mrg/mysql-5.0-opt


sql/sql_select.cc:
  Auto merged

into  mysql.com:/home/hf/work/mrg/mysql-5.0-opt

mysql-test/r/view.result:
  merging

into  mysql.com:/home/hf/work/mrg/mysql-5.0-opt


mysql-test/r/order_by.result:
  Auto merged
mysql-test/r/subselect.result:
  Auto merged
mysql-test/t/order_by.test:
  Auto merged
mysql-test/t/sp.test:
  Auto merged
sql/item.cc:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/item_cmpfunc.h:
  Auto merged
sql/item_func.cc:
  Auto merged
sql/mysql_priv.h:
  Auto merged
sql/sql_base.cc:
  Auto merged
sql/sql_insert.cc:
  Auto merged
sql/sql_lex.cc:
  Auto merged
sql/sql_lex.h:
  Auto merged
sql/sql_load.cc:
  Auto merged
sql/sql_parse.cc:
  Auto merged
sql/sql_select.cc:
  Auto merged
sql/sql_update.cc:
  Auto merged
mysql-test/r/func_str.result:
  merging
mysql-test/r/sp.result:
  merging
mysql-test/r/view.result:
  merging
mysql-test/t/func_str.test:
  merging
mysql-test/t/view.test:
  merging

into  mysql.com:/home/hf/work/mrg/mysql-4.1-opt

  Postfix for bug#22331.


sql/sql_select.cc:
  Postfix for bug#22331.

into  pilot.blaudden:/home/msvensson/mysql/mysql-4.1-maint

into  pilot.blaudden:/home/msvensson/mysql/mysql-5.0-maint


mysql-test/mysql-test-run.pl:
  Manual merge

into  pilot.blaudden:/home/msvensson/mysql/mysql-5.0-maint


extra/comp_err.c:
  Auto merged
sql/mysqld.cc:
  Auto merged

comp_err.c:  return ha_checksum from checksum_format_specifier() - more correct, avoid a compiler warning


extra/comp_err.c:
  return ha_checksum from checksum_format_specifier() - more correct, avoid a compiler warning

into  mysql.com:/data0/mysqldev/users/tomas/mysql-5.0-maint

into  poseidon.mysql.com:/home/tomas/mysql-5.0-ndb

into  quadxeon.mysql.com:/benchmarks/ext3/TOSAVE/tsmith/bk/maint/mar07/stage2/50

into  quadxeon.mysql.com:/benchmarks/ext3/TOSAVE/tsmith/bk/maint/mar07/stage2/50

into  quadxeon.mysql.com:/benchmarks/ext3/TOSAVE/tsmith/bk/maint/mar07/stage2/41

into  quadxeon.mysql.com:/benchmarks/ext3/TOSAVE/tsmith/bk/maint/mar07/stage2/50


scripts/make_binary_distribution.sh:
  Auto merged

into  quadxeon.mysql.com:/benchmarks/ext3/TOSAVE/tsmith/bk/maint/mar07/stage2/41

into  quadxeon.mysql.com:/benchmarks/ext3/TOSAVE/tsmith/bk/maint/mrg0306/50


sql/mysqld.cc:
  Auto merged
sql/sql_class.cc:
  Auto merged
sql/sql_class.h:
  Auto merged
sql/sql_parse.cc:
  Auto merged