documentation
While the manual mentions FRAC_SECOND only for the TIMESTAMPADD()
function, it was also possible to use FRAC_SECOND with DATE_ADD(),
DATE_SUB() and +/- INTERVAL.
Fixed the parser to match the manual, i.e. using FRAC_SECOND for
anything other than TIMESTAMPADD()/TIMESTAMPDIFF() now produces a
syntax error.
Additionally, the patch allows MICROSECOND to be used in TIMESTAMPADD/
TIMESTAMPDIFF and marks FRAC_SECOND as deprecated.
between 5.0 and 5.1.
The problem was that in the patch for Bug#11986 it was decided
to store original query in UTF8 encoding for the INFORMATION_SCHEMA.
This approach however turned out to be quite difficult to implement
properly. The main problem is to preserve the same IS-output after
dump/restore.
So, the fix is to rollback to the previous functionality, but also
to fix it to support multi-character-set-queries properly. The idea
is to generate INFORMATION_SCHEMA-query from the item-tree after
parsing view declaration. The IS-query should:
- be completely in UTF8;
- not contain character set introducers.
For more information, see WL4052.
The problem is that when a stored procedure is being parsed for
the first execution, the body is copied to a temporary buffer
which is disregarded sometime after the statement is parsed.
And during this parsing phase, the rule for CREATE VIEW was
holding a reference to the string being parsed for use during
the execution of the CREATE VIEW statement, leading to invalid
memory access later.
The solution is to allocate and copy the SELECT of a CREATE
VIEW statement using the thread memory root, which is set to
the permanent arena of the stored procedure.
but not collation.
The problem here was that text literals in a view were always
dumped with character set introducer. That lead to loosing
collation information.
The fix is to dump character set introducer only if it was
in the original query. That is now possible because there
is no problem any more of loss of character set of string
literals in views -- after WL#4052 the view is dumped
in the original character set.
on table creates
The problem was in incompatible syntax for key definition in CREATE
TABLE.
5.0 supports only the following syntax for key definition (see "CREATE
TABLE syntax" in the manual):
{INDEX|KEY} [index_name] [index_type] (index_col_name,...)
While 5.1 parser supports the above syntax, the "preferred" syntax was
changed to:
{INDEX|KEY} [index_name] (index_col_name,...) [index_type]
The above syntax is used in 5.1 for the SHOW CREATE TABLE output, which
led to dumps generated by 5.1 being incompatible with 5.0.
Fixed by changing the parser in 5.0 to support both 5.0 and 5.1 syntax
for key definition.
Bug 33983 (Stored Procedures: wrong end <label> syntax is accepted)
The server used to crash when REPEAT or another control instruction
was used in conjunction with labels and a LEAVE instruction.
The crash was caused by a missing "pop" of handlers or cursors in the
code representing the stored program. When executing the code in a loop,
this missing "pop" would result in a stack overflow, corrupting memory.
Code generation has been fixed to produce the missing h_pop/c_pop
instructions.
Also, the logic checking that labels at the beginning and the end of a
statement are matched was incorrect, causing Bug 33983.
End labels, when used, must match the label used at the beginning of a block.
Parser rejects ODBC's escape sequences for outer joins other
than left outer join, yet the escape sequence BNF specifies
that this syntax can be used for left, right, and full outer
join syntax.
The problem is that although the MySQL Connector/ODBC advertises
"Outer Join Escape Sequence" capabilities, the parsing is done
in the server and historically it only supported this syntax
for left outer joins and applications such as Crystal Reports
11 tries to use this syntax for inner joins.
The chosen solution is to reorganize a couple of parser rules
to ignore any kind of SQL escape sequence. Ignoring the escape
sequences is harmless because the various SQL join clauses
are supported by the server.
In a union without braces, the order by at the end is applied to the
overall union. It therefore should not interfere with the individual
select parts of the union.
Fixed by changing our parser rules appropriately.
subselects into account
It is forbidden to use the SELECT INTO construction inside UNION statements
unless on the last SELECT of the union. The parser records whether it
has seen INTO or not when parsing a UNION statement. But if the INTO was
legally used in an outer query, an error is thrown if UNION is seen in a
subquery. Fixed in 5.0 by remembering the nesting level of INTO tokens and
mitigate the error unless it collides with the UNION.
Anti-patch. This patch undoes the previously pushed patch. It is
null-merged in versions 5.1 and above since there the original
patch is still desired.
Parser rejects valid INTERVAL() expressions when associated with
arithmetic operators. The problem is the way in which the expression
and interval grammar rules were organized caused shift/reduce conflicts.
The solution is to tweak the interval rules to avoid shift/reduce
conflicts by removing the broken interval_expr rule and explicitly
specify it's content where necessary.
Original fix by Davi Arnaut, revised and improved rules by Marc Alff
crashes MySQL 5.122
There was a difference in how UNIONs are handled
on top level and when in sub-query.
Because the rules for sub-queries were syntactically
allowing cases that are not currently supported by
the server we had crashes (this bug) or wrong results
(bug 32051).
Fixed by making the syntax rules for UNIONs match the
ones at top level.
These rules however do not support nesting UNIONs, e.g.
(SELECT a FROM t1 UNION ALL SELECT b FROM t2)
UNION
(SELECT c FROM t3 UNION ALL SELECT d FROM t4)
Supports for statements with nested UNIONs will be
added in a future version.
Problem: we have CHECK TABLE options allowed (by accident?) for
ANALYZE/OPTIMIZE TABLE.
Fix: disable them.
Note: it might require additional fixes in 5.1/6.0
When the server was out of memory it crashed because of invalid memory access.
This patch adds detection for failed memory allocations and make the server
output a proper error message.
