1. Fix index access costs for MERGE tables, set block_size=myisam_block_size/#underlying_tables 
   instead of 0 which it was before.
2. Make index scans on MERGE table to return records in (key_tuple, merge_table_rowid) order, 
   instead of just (key_tuple) order. This makes an index scan on MERGE table to be truly a ROR-scan
   which is a requirement for index_merge union/intersection.

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

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

Bug #17158  	load data infile of char values into table of char with no (PK) fails to load
Bug #17081  	Doing "LOAD DATA INFILE" directly after delete can cause missing data

into  rurik.mysql.com:/home/igor/dev/mysql-5.0-0

If check_quick_select returns non-empty range then the function cost_group_min_max
cannot return 0 as an estimate of the number of retrieved records.
Yet the function erroneously returned 0 as the estimate in some situations.

into  mysql.com:/extern/mysql/work/bug16303/mysql-5.0

into  mysql.com:/extern/mysql/work/bug16303/mysql-5.0

into  mysql.com:/extern/mysql/work/bug16568/mysql-5.0

into  mysql.com:/space/pekka/ndb/version/my50

into  mysql.com:/space/pekka/ndb/version/my50

into  rurik.mysql.com:/home/igor/dev/mysql-5.0-0

into  rurik.mysql.com:/home/igor/dev/mysql-5.0-0

into  rurik.mysql.com:/home/igor/dev/mysql-4.1-0

into  rurik.mysql.com:/home/igor/mysql-5.0

into  rurik.mysql.com:/home/igor/dev/mysql-5.0-0

into  mysql.com:/opt/local/work/mysql-5.0-root

  manual adding the fix for bug#15828 which did not automerge

into  mysql.com.:/data/BK/mysql-5.0_15828

into  mysql.com:/opt/local/work/mysql-5.0-root

(No change of functionality)

into  neptunus.(none):/home/msvensson/mysql/mysql-5.0

into  neptunus.(none):/home/msvensson/mysql/mysql-5.0

When an ambiguous field name is used in a group by clause a warning is issued
in the find_order_in_list function by a call to push_warning_printf.
An expression that was not always valid was passed to this call as the field
name parameter.

into  mysql.com:/extern/mysql/work/bug15011/mysql-5.0

Added comments.

into  neptunus.(none):/home/msvensson/mysql/mysql-5.0