(4.1 version, with post-review fixes)
The fix for another Bug (6439) limited FROM_UNIXTIME() to
TIMESTAMP_MAX_VALUE which is 2145916799 or 2037-12-01 23:59:59 GMT,
however unix timestamp in general is not considered to be limited
by this value. All dates up to power(2,31)-1 are valid.
This patch extends allowed TIMESTAMP range so, that max
TIMESTAMP value is power(2,31)-1. It also corrects
FROM_UNIXTIME() and UNIX_TIMESTAMP() functions, so that
max allowed UNIX_TIMESTAMP() is power(2,31)-1. FROM_UNIXTIME()
is fixed accordingly to allow conversion of dates up to
2038-01-19 03:14:07 UTC. The patch also fixes CONVERT_TZ()
function to allow extended range of dates.
The main problem solved in the patch is possible overflows
of variables, used in broken-time representation to time_t
conversion (required for UNIX_TIMESTAMP).
From the manual:
date arithmetic operations require complete dates and do not work with
incomplete dates such as '2006-07-00' or badly malformed dates.
- bug #11655 "Wrong time is returning from nested selects - maximum time exists
- input and output TIME values were not validated properly in several conversion functions
- bug #20927 "sec_to_time treats big unsigned as signed"
- integer overflows were not checked in several functions. As a result, input values like 2^32 or 3600*2^32 were treated as 0
- BIGINT UNSIGNED values were treated as SIGNED in several functions
- in cases where both input string truncation and out-of-range TIME value occur, only 'truncated incorrect time value' warning was produced
- Type casting was not consequent, thus when adding a DATE type with
a WEEK interval the result type was DATETIME and not DATE as is the
norm.
- By changing the order of the date internal enumerations the deviant
type casting is resolved (Item_date_add_interval::fix_length_and_dec()
which determines result type for this operation assumes that addition
of any interval with value <= INTERVAL_DAY to date value will result
in date). There are two independant places to change:
interval_names[] and interval_type.
Corrected test case after removal of fix for bug#16377
type_date.test:
Corrected test case after removal of fix for bug#16377
item_cmpfunc.cc:
Removed changes to the agg_cmp_type() made in the for bug#16377
Variable character_set_results can legally be NULL (for "no conversion.")
This could result in a NULL deref that crashed the server. Fixed.
(Although ran some additional precursory tests to see whether I could break
anything else, but no breakage so far.)
into salvation.intern.azundris.com:/home/tnurnberg/21913/my50-21913
21913: DATE_FORMAT() Crashes mysql server if I use it through mysql-connector-j driver.
Variable character_set_results can legally be NULL (for "no conversion.")
This could result in a NULL deref that crashed the server. Fixed.
(Although ran some additional precursory tests to see whether I could break
anything else, but no breakage so far.)
Variable character_set_results can legally be NULL (for "no conversion.")
This could result in a NULL deref that crashed the server. Fixed.
(Although ran some additional precursory tests to see whether I could break
anything else, but no breakage so far.)
time_format() claimed %H and %k would return at most two digits
(hours 0-23), but this coincided neither with actual behaviour
nor with docs. this is not visible in simple queries; forcing
a temp-table is probably the easiest way to see this. adjusted
the return-length appropriately; the alternative would be to
adjust the docs to say that behaviour for > 99 hours is undefined.
---
Bug#19844: time_format in Union truncates values
time_format() claimed %H and %k would return at most two digits
(hours 0-23), but this coincided neither with actual behaviour
nor with docs. this is not visible in simple queries; forcing
a temp-table is probably the easiest way to see this. adjusted
the return-length appropriately; the alternative would be to
adjust the docs to say that behaviour for > 99 hours is undefined.
difference between timestamp in values of months and quarters.)
Problem: when requesting timestamp diff in months or quarters, it
would only examine the date (and not the time) for the comparison.
Solution: increased precision of comparison.
The problem was that we restored SQL_CACHE, SQL_NO_CACHE flags in SELECT
statement from internal structures based on value set later at runtime, not
the original value set by the user.
The solution is to remember that original value.
- The setting of "ENV{'TZ'}" doesn't affect the timezone
used by MySQL Server on Windows.
- Explicitly set timezone to "+03:00" in test case before
doing the calculatiosn to check that there is three hours
difference between utc and local time.
(Magnus' fix)
can lead to a wrong result.
All date/time functions has the STRING result type thus their results are
compared as strings. The string date representation allows a user to skip
some of leading zeros. This can lead to wrong comparison result if a date/time
function result is compared to such a string constant.
The idea behind this bug fix is to compare results of date/time functions
and data/time constants as ints, because that date/time representation is
more exact. To achieve this the agg_cmp_type() is changed to take in the
account that a date/time field or an date/time item should be compared
as ints.
This bug fix is partially back ported from 5.0.
The agg_cmp_type() function now accepts THD as one of parameters.
In addition, it now checks if a date/time field/function is present in the
list. If so, it tries to coerce all constants to INT to make date/time
comparison return correct result. The field for the constant coercion is
taken from the Item_field or constructed from the Item_func. In latter case
the constructed field will be freed after conversion of all constant items.
Otherwise the result is same as before - aggregated with help of the
item_cmp_type() function.
From the Item_func_between::fix_length_and_dec() function removed the part
which was converting date/time constants to int if possible. Now this is
done by the agg_cmp_type() function.
The new function result_as_longlong() is added to the Item class.
It indicates that the item is a date/time item and result of it can be
compared as int. Such items are date/time fields/functions.
Correct val_int() methods are implemented for classes Item_date_typecast,
Item_func_makedate, Item_time_typecast, Item_datetime_typecast. All these
classes are derived from Item_str_func and Item_str_func::val_int() converts
its string value to int without regard to the date/time type of these items.
Arg_comparator::set_compare_func() and Arg_comparator::set_cmp_func()
functions are changed to substitute result type of an item with the INT_RESULT
if the item is a date/time item and another item is a constant. This is done
to get a correct result of comparisons like date_time_function() = string_constant.
If the second or the third argument of a BETWEEN predicate was
a constant expression, like '2005.09.01' - INTERVAL 6 MONTH,
while the other two arguments were fields then the predicate
was evaluated incorrectly and the query returned a wrong
result set.
The bug was introduced in 5.0.17 when in the fix for 12612.
