on large length
Problem: Most (all) of the numeric inputs were being coerced into
int (32 bit) sized variables. Works OK for sane inputs; any input
larger than 2^32 (or 2^31 for signed vars) exihibited predictable
wrapping behavior (up to about 10^18) and then started having really
strange behaviour past that point (since the conversion to 64 bit int
from the DECIMAL type can do weird things on out of range numbers).
Solution: 1) Add many tests. 2) Convert input from (u)long type to
(u)longlong. 3) Do (sometimes multiple) sanity checks on input,
keeping in mind that sometimes a negative longlong is not a negative
longlong (if the unsigned_flag is set). 4) Emulate existing behavior
w/rt negative and "small" out-of-bounds values.
The Item_func_mod objects never had maybe_null set, so users had no reason
to expect that they can be NULL, and may therefore deduce wrong results.
Now, set maybe_null.
decimal->ulong conversion fixed to assign max possible ULONG if decimal
is bigger
Item_func_unsigned now handles DECIMAL parameter separately as we can't
rely on decimal::val_int result here.
select OK.
The SQL parser was using Item::name to transfer user defined function attributes
to the user defined function (udf). It was not distinguishing between user defined
function call arguments and stored procedure call arguments. Setting Item::name
was causing Item_ref::print() method to print the argument as quoted identifiers
and caused views that reference aggregate functions as udf call arguments (and
rely on Item::print() for the text of the view to store) to throw an undefined
identifier error.
Overloaded Item_ref::print to print aggregate functions as such when printing
the references to aggregate functions taken out of context by split_sum_func2()
Fixed the parser to properly detect using AS clause in stored procedure arguments
as an error.
Fixed printing the arguments of udf call to print properly the udf attribute.
Note: bug#21726 does not directly apply to 4.1, as it doesn't have stored
procedures. However, 4.1 had some bugs that were fixed in 5.0 by the
patch for bug#21726, and this patch is a backport of those fixes.
Namely, in 4.1 it fixes:
- LAST_INSERT_ID(expr) didn't return value of expr (4.1 specific).
- LAST_INSERT_ID() could return the value generated by current
statement if the call happens after the generation, like in
CREATE TABLE t1 (i INT AUTO_INCREMENT PRIMARY KEY, j INT);
INSERT INTO t1 VALUES (NULL, 0), (NULL, LAST_INSERT_ID());
- Redundant binary log LAST_INSERT_ID_EVENTs could be generated.
invocations of LAST_INSERT_ID.
Reding of LAST_INSERT_ID inside stored function wasn't noted by caller,
and no LAST_INSERT_ID_EVENT was issued for binary log.
The solution is to add THD::last_insert_id_used_bin_log, which is much
like THD::last_insert_id_used, but is reset only for upper-level
statements. This new variable is used to issue LAST_INSERT_ID_EVENT.
Non-upper-level INSERTs (the ones in the body of stored procedure,
stored function, or trigger) into a table that have AUTO_INCREMENT
column didn't affected the result of LAST_INSERT_ID() on this level.
The problem was introduced with the fix of bug 6880, which in turn was
introduced with the fix of bug 3117, where current insert_id value was
remembered on the first call to LAST_INSERT_ID() (bug 3117) and was
returned from that function until it was reset before the next
_upper-level_ statement (bug 6880).
The fix for bug#21726 brings back the behaviour of version 4.0, and
implements the following: remember insert_id value at the beginning
of the statement or expression (which at that point equals to
the first insert_id value generated by the previous statement), and
return that remembered value from LAST_INSERT_ID() or @@LAST_INSERT_ID.
Thus, the value returned by LAST_INSERT_ID() is not affected by values
generated by current statement, nor by LAST_INSERT_ID(expr) calls in
this statement.
Version 5.1 does not have this bug (it was fixed by WL 3146).
- Honor unsigned_flag in the corresponding functions
- Use compare_int_signed_unsigned()/compare_int_unsigned_signed() instead of explicit comparison in GREATEST() and LEAST()
equal constant under any circumstances.
In fact this substitution can be allowed if the field is
not of a type string or if the field reference serves as
an argument of a comparison predicate.
used.
Sorting by RAND() uses a temporary table in order to get a correct results.
User defined variable was set during filling the temporary table and later
on it is substituted for its value from the temporary table. Due to this
it contains the last value stored in the temporary table.
Now if the result_field is set for the Item_func_set_user_var object it
updates variable from the result_field value when being sent to a client.
The Item_func_set_user_var::check() now accepts a use_result_field
parameter. Depending on its value the result_field or the args[0] is used
to get current value.
When there is no index defined filesort is used to sort the result of a
query. If there is a function in the select list and the result set should be
ordered by it's value then this function will be evaluated twice. First time to
get the value of the sort key and second time to send its value to a user.
This happens because filesort when sorts a table remembers only values of its
fields but not values of functions.
All functions are affected. But taking into account that SP and UDF functions
can be both expensive and non-deterministic a temporary table should be used
to store their results and then sort it to avoid twice SP evaluation and to
get a correct result.
If an expression referenced in an ORDER clause contains a SP or UDF
function, force the use of a temporary table.
A new Item_processor function called func_type_checker_processor is added
to check whether the expression contains a function of a particular type.
