+ Fix for Bug#43114 wait_until_count_sessions too restrictive, random PB failures
+ Removal of a lot of other weaknesses found
+ modifications according to review
return no rows
The algorithm of determining the best key for loose index scan is doing a loop
over the available indexes and selects the one that has the best cost.
It retrieves the parameters of the current index into a set of variables.
If the cost of using the current index is lower than the best cost so far it
copies these variables into another set of variables that contain the
information for the best index so far.
After having checked all the indexes it uses these variables (outside of the
index loop) to create the table read plan object instance.
The was a single omission : the key_infix/key_infix_len variables were used
outside of the loop without being preserved in the loop for the best index
so far.
This causes these variables to get overwritten by the next index(es) checked.
Fixed by adding variables to hold the data for the current index, passing
the new variables to the function that assigns values to them and copying
the new variables into the existing ones when selecting a new current best
index.
To avoid further such problems moved the declarations of the variables used
to keep information about the current index inside the loop's compound
statement.
Started fix in 5.0 as the same issue is here.
Revising queries used given what appears to be the scope of this test to only select the manipulated variables.
Added tests for values that are / are not multiples of 1024 to test rounding / constraints.
This behavior is not currently documented (docs bug has been opened)
There was a problem when a DELIMITER COMMAND is not the first
command on the line. I this case an extra line feed was added
to the glob buffer and this was causing subsequent attempts
to enter this delimiter to fail.
Fixed by not adding a new line to the glob buffer if the
command being added is a DELIMITER
There was a problem when a DELIMITER COMMAND is not the first
command on the line. I this case an extra line feed was added
to the glob buffer and this was causing subsequent attempts
to enter this delimiter to fail.
Fixed by not adding a new line to the glob buffer if the
command being added is a DELIMITER
Bug#41112: crash in mysql_ha_close_table/get_lock_data with alter table
The problem is that the server wasn't handling robustly failures
to re-open a table during a HANDLER .. READ statement. If the
table needed to be re-opened due to it's storage engine being
altered to one that doesn't support HANDLER, a reference (dangling
pointer) to a closed table could be left in place and accessed in
later attempts to fetch from the table using the handler. Also,
if the server failed to set a error message if the re-open
failed. These problems could lead to server crashes or hangs.
The solution is to remove any references to a closed table and
to set a error if reopening a table during a HANDLER .. READ
statement fails.
Both of our own implementations of rint(3) were inconsistent with the
most common behavior of rint() on those platforms that have it: round
to nearest, break ties by rounding to nearest even.
Fixed by leaving just one implementation of rint() in our source tree,
and changing its behavior to match the most common native
implementations on other platforms.
