Only for qc_sqlite.
After a second look qc_mysqlembedded will not support dupping
the statement information. Without additional changes, simply stashing
an info object away, parsing another new GWBUF, deleting that and
then using the stashed away info object will not work; the THD object
will be corrupted. As qc_mysqlembedded is _only_ used for verifying the
sqlite-based parser this is not important anyway.
The query classifier stores information about the statement carried
by a GWBUF in the GWBUF itself. We need to be able to store that
object out side the lifetime of the GWBUF. So, we require that a
query classifier is capable of duplicating references to that object.
sqlite does not treat # as the start of a to-end-of-line
comment. It cannot trivially be treated as such because at
startup sqlite parses statements containing the #-character.
Thus, only after sqlite has been initialized can it be treated
the same way as --.
The two operations return different types of results and need to be
treated differently in order for them to be handled correctly in 2.2.
This fixes the unexpected internal state errors that happened in all 2.2
versions due to a wrong assumption made by readwritesplit. This fix is not
necessary for newer versions as the LOAD DATA LOCAL INFILE processing is
done with a simpler, and more robust, method.
After a temporary table is created, readwritesplit will check whether a
query drops or targets that temporary table. The check for query type was
missing from the table dropping part of the code. The temporary table read
part was checking that the query is a text form query.
Added a debug assertion to the query parsing function in qc_sqlite to
catch this type of interface misuse.
When the parsing of a query failed, the message would treat the parameter
as a string as the printf format was `%*s` instead of `%.*s`.
The manpage of printf states the following about the precision specifier:
... or the maximum number of characters to be printed from a string
for `s` and `S` conversions.
This means that the field length specifier is somewhat meaningless for
strings.
If the API versions do not match, MaxScale will treat this as an
error. The API versioning would allow backwards compatible changes but the
functionality to handle that is not implemented in MaxScale.
Updated API versions based on changes done to module APIs in 2.2.
Since the thread initialization was removed from the process
initialization function, the thread finish function should not be called
in the process finish function.
By moving the initialization into Worker::run, all threads, including the
main thread, are properly initialized. This was not noticed before as
qc_sqlite initialized the main thread in the process initialization
callback.
The enums exposed by the connector are not intended to be used by the
users of the library. The fact that the protocol, and other, modules used
it was in violation of how the library is intended to be used.
Adding an internal mapping into MaxScale also removes some of the
dependencies that the core has on the connector.
Cleaned up the MaxScale version of the mysql.h header by removing all
unused includes. This revealed a large amount of dependencies on these
removed includes in other files which needed to be fixed.
Also sorted all includes in changed files by type and alphabetical
order. Removed explicit revision history from modified files.
We are only interested in asterisks and column names. Everything
else - integers, floating point numbers, strings, etc. - is of
no interest and not an error.
In qc_sqlite the fields that a particular function refers to are now
collected and reported. Qc_mysqlembedded needs to be updated accordingly
and also the compare utility. For subsequent commits.
In case of very large compound selects or an INSERT with many
values, qc_sqlite could run out of stack space. To deal with
that, the critical recursion is turned into an iteration.
Alias handling must be made so that in a subselect, aliases created
in an outer select are available, but aliases created in another
subselect are not.
The sqlite3 initialization is done a bit more properly now.
It is also ensured that issues are logged at most once, even
if a statement is parsed twice.
All callbacks called by sqlite now only access the thread specific
QcSqliteInfo and call the corresponding function on that instance.
This is the first step in making qc_sqlite exception safe from the
point of view of sqlite3.
As the diff is confusing, basically the ONLY thing that has been
done is:
BEFORE:
-------
class QcSqliteInfo
{
...
};
static void some_helper(...) { ... }
void mxs_someCallback(...)
{
QC_TRACE();
QcSqliteInfo* info = this_thread.pInfo;
ss_dassert(info);
info->m_status = ...;
some_helper(info, ...);
}
AFTER:
------
class QcSqliteInfo
{
...
void some_helper(...) { ... }
void mxs_someCallback(...)
{
m_status = ...;
some_helper(this, ...);
}
};
void mxs_someCallback(...)
{
QC_TRACE();
QcSqliteInfo* pInfo = this_thread.pInfo;
ss_dassert(pInfo);
pInfo->mxs_someCallback(...);
}
With this change, for a statement like
SELECT t2.a FROM t1 t2;
the affected field is reported as t1.a and not as t2.a, as it
was before.
For a statement like
SELECT t.f FROM d.t;
qc_mysqlembedded will now return "d.t.f" as the affected field,
while qc_sqlite will still return "t.f" as both implementations did
before. In qc_mysqlembedded's case that is a side-effect of the
alias handling. To get qc_sqlite to return the same (which would
be good), the table names would have to be collected in a smarter
way than they are now.
Alias names for tables are now collected, so that the true
table name of a referred to field can be reported. That modification
will be made in a subsequent commit.
