MySQL Reference Manual for version 4.0.18.
1.6.5 New Features Planned for the Mid-Term Future
-
Implement function:
get_changed_tables(timeout,table1,table2,...)
.
-
Change reading through tables to use memmap when possible. Now only
compressed tables use memmap.
-
Make the automatic timestamp code nicer. Add timestamps to the update
log with
SET TIMESTAMP=#;
.
-
Use read/write mutex in some places to get more speed.
-
Simple views (implemented in stepwise fashion up to full functionality).
See section 1.8.5.6 Views.
-
Automatically close some tables if a table, temporary table, or temporary file
gets error 23 (too many open files).
-
Better constant propagation. When an occurrence of
col_name=n
is found in an expression, for some constant n
, replace other
occurrences of col_name
within the expression with n
.
Currently, this is done only for some simple cases.
-
Change all const expressions with calculated expressions if possible.
-
Optimize key = expression comparisons. At the moment only key = field or
key = constant comparisons are optimized.
-
Join some of the copy functions for nicer code.
-
Change `sql_yacc.yy' to an inline parser to reduce its size and get
better error messages.
-
Change the parser to use only one rule per different number of arguments
in function.
-
Use of full calculation names in the order part (for ACCESS97).
-
MINUS
, INTERSECT
, and FULL OUTER JOIN
.
(Currently UNION
[in 4.0] and LEFT|RIGHT OUTER JOIN
are supported.)
-
Allow
SQL_OPTION MAX_SELECT_TIME=#
, for placing a time limit on a query.
-
Allow updates to be logged to a database.
-
Enhance
LIMIT
to allow retrieval of data from the end of a result set.
-
Alarm around client connect/read/write functions.
-
Please note the changes to
mysqld_safe
: according to FSSTND (which
Debian tries to follow) PID files should go into `/var/run/<progname>.pid'
and log files into `/var/log'. It would be nice if you could put the
"DATADIR" in the first declaration of "pidfile" and "log", so the
placement of these files can be changed with a single statement.
-
Allow a client to request logging.
-
Allow the
LOAD DATA INFILE
statement
to read files that have been compressed with gzip
.
-
Fix sorting and grouping of
BLOB
columns (partly solved now).
-
Change to use semaphores when counting threads. One should first implement
a semaphore library for MIT-pthreads.
-
Add full support for
JOIN
with parentheses.
-
As an alternative to the one-thread-per-connection model, manage a pool
of threads to handle queries.
-
Allow
GET_LOCK()
to obtain more than one lock. When doing this,
one must also handle the possible deadlocks this change will introduce.
This document was generated
by rdg (Feb 25 2004)
using texi2html