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manual.texi British-ise some -ize words
manual.texi formatting fixups Docs/manual.texi: British-ise some -ize words
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@ -14933,7 +14933,7 @@ system. This section describes how it works.
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Anyone using MySQL on a computer connected to the Internet
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should read this section to avoid the most common security mistakes.
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In discussing security, we emphasize the necessity of fully protecting the
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In discussing security, we emphasise the necessity of fully protecting the
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entire server host (not simply the MySQL server) against all types
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of applicable attacks: eavesdropping, altering, playback, and denial of
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service. We do not cover all aspects of availability and fault tolerance
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@ -19647,7 +19647,7 @@ is high, it is a good indication that your queries and tables are properly index
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@item @code{Handler_read_next} @tab Number of requests to read next row in key order. This
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will be incremented if you are querying an index column with a range constraint. This also
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will be incremented if you are doing an index scan.
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@item @code{Handler_read_prev} @tab Number of requests to read previous row in key order. This is mainly used to optimize @code{ORDER BY ... DESC}.
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@item @code{Handler_read_prev} @tab Number of requests to read previous row in key order. This is mainly used to optimise @code{ORDER BY ... DESC}.
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@item @code{Handler_read_rnd} @tab Number of requests to read a row based on a fixed position.
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This will be high if you are doing a lot of queries that require sorting of the result.
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@item @code{Handler_read_rnd_next} @tab Number of requests to read the next row in the datafile.
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@ -23672,7 +23672,7 @@ For more details, please see @ref{Replication FAQ}.
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If you want to become a real MySQL replication guru, we suggest that you
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begin by studying, pondering, and trying all commands
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mentioned in @ref{Replication SQL}. You should also familiarize yourself
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mentioned in @ref{Replication SQL}. You should also familiarise yourself
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with replication startup options in @file{my.cnf} in
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@ref{Replication Options}.
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@ -23960,7 +23960,7 @@ the slave. The other bug is that if the ignored table gets partially
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updated, the slave thread will not notice that the table actually should
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have been ignored and will suspend the replication process. While the
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above bugs are conceptually very simple to fix, we have not yet found a way
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to do this without a sigficant code change that would compromize the stability
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to do this without a significant code change that would compromise the stability
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status of 3.23 branch. There exists a workaround for both if in the rare case
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it happens to affect your application -- use @code{slave-skip-errors}.
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@end itemize
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@ -25473,7 +25473,7 @@ this join type is good.
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Only rows that are in a given range will be retrieved, using an index to
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select the rows. The @code{key} column indicates which index is used.
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The @code{key_len} contains the longest key part that was used.
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The @code{ref} column will be NULL for this type.
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The @code{ref} column will be @code{NULL} for this type.
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@item index
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This is the same as @code{ALL}, except that only the index tree is
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@ -25764,8 +25764,9 @@ Constant condition removal (needed because of constant folding):
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Constant expressions used by indexes are evaluated only once.
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@item
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@code{COUNT(*)} on a single table without a @code{WHERE} is retrieved
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directly from the table information for MyISAM and HEAP tables. This is
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also done for any @code{NOT NULL} expression when used with only one table.
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directly from the table information for @code{MyISAM} and @code{HEAP} tables.
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This is also done for any @code{NOT NULL} expression when used with only one
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table.
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@item
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Early detection of invalid constant expressions. MySQL quickly
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detects that some @code{SELECT} statements are impossible and returns no rows.
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@ -25876,9 +25877,9 @@ the scanning of the not used tables as soon as it has found the first match.
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SELECT DISTINCT t1.a FROM t1,t2 where t1.a=t2.a;
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@end example
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In the case, assuming t1 is used before t2 (check with @code{EXPLAIN}), then
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MySQL will stop reading from t2 (for that particular row in t1)
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when the first row in t2 is found.
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In the case, assuming @code{t1} is used before @code{t2} (check with
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@code{EXPLAIN}), then MySQL will stop reading from @code{t2} (for that
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particular row in @code{t1}) when the first row in @code{t2} is found.
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@node LEFT JOIN optimisation, ORDER BY optimisation, DISTINCT optimisation, Query Speed
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@ -25996,7 +25997,7 @@ do the @code{ORDER BY}:
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@item
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You are joining many tables and the columns you are doing an @code{ORDER
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BY} on are not all from the first not-const table that is used to
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BY} on are not all from the first not-@code{const} table that is used to
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retrieve rows (This is the first table in the @code{EXPLAIN} output which
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doesn't use a @code{const} row fetch method).
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@ -26021,7 +26022,7 @@ algorithm:
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@itemize @bullet
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@item
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Read all rows according to key or by table scanning.
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Rows that doesn't match the WHERE clause are skipped.
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Rows that don't match the @code{WHERE} clause are skipped.
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@item
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Store the sort-key in a buffer (of size @code{sort_buffer}).
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@item
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@ -26196,11 +26197,11 @@ flush-tables}.
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Note that @code{LOAD DATA INFILE} also does the above optimisation if
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you insert into an empty table; the main difference with the above
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procedure is that you can let myisamchk allocate much more temporary
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procedure is that you can let @code{myisamchk} allocate much more temporary
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memory for the index creation that you may want MySQL to allocate for
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every index recreation.
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Since @strong{MySQL 4.0} you can also use
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Since MySQL 4.0 you can also use
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@code{ALTER TABLE tbl_name DISABLE KEYS} instead of
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@code{myisamchk --keys-used=0 -rq /path/to/db/tbl_name} and
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@code{ALTER TABLE tbl_name ENABLE KEYS} instead of
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@ -26303,8 +26304,8 @@ Always check that all your queries really use the indexes you have created
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in the tables. In MySQL you can do this with the @code{EXPLAIN}
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command. @xref{EXPLAIN, Explain, Explain, manual}.
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@item
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Try to avoid complex @code{SELECT} queries on MyISAM tables that are updated a
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lot. This is to avoid problems with table locking.
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Try to avoid complex @code{SELECT} queries on @code{MyISAM} tables that are
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updated a lot. This is to avoid problems with table locking.
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@item
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The new @code{MyISAM} tables can insert rows in a table without deleted
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rows at the same time another table is reading from it. If this is important
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@ -26312,7 +26313,7 @@ for you, you should consider methods where you don't have to delete rows
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or run @code{OPTIMIZE TABLE} after you have deleted a lot of rows.
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@item
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Use @code{ALTER TABLE ... ORDER BY expr1,expr2...} if you mostly
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retrieve rows in expr1,expr2... order. By using this option after big
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retrieve rows in @code{expr1,expr2...} order. By using this option after big
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changes to the table, you may be able to get higher performance.
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@item
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In some cases it may make sense to introduce a column that is 'hashed'
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@ -26342,7 +26343,8 @@ introduce a new table and update the counter in real time. An update of
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type @code{UPDATE table set count=count+1 where index_column=constant}
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is very fast!
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This is really important when you use databases like MySQL that
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This is really important when you use MySQL table types like MyISAM and
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ISAM that
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only have table locking (multiple readers / single writers). This will
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also give better performance with most databases, as the row locking
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manager in this case will have less to do.
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@ -26580,7 +26582,7 @@ As updates on tables normally are considered to be more important than
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than statements that retrieve information from a table. This should
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ensure that updates are not 'starved' because one issues a lot of heavy
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queries against a specific table. (You can change this by using
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LOW_PRIORITY with the statement that does the update or
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@code{LOW_PRIORITY} with the statement that does the update or
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@code{HIGH_PRIORITY} with the @code{SELECT} statement.)
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Starting from MySQL Version 3.23.7 one can use the
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@ -26625,7 +26627,7 @@ You can give a specific @code{INSERT}, @code{UPDATE}, or @code{DELETE}
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statement lower priority with the @code{LOW_PRIORITY} attribute.
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@item
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Start @code{mysqld} with a low value for @strong{max_write_lock_count} to give
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Start @code{mysqld} with a low value for @code{max_write_lock_count} to give
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@code{READ} locks after a certain number of @code{WRITE} locks.
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@item
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@ -26750,7 +26752,7 @@ having it on all columns by default.
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If you don't have any variable-length columns (@code{VARCHAR},
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@code{TEXT}, or @code{BLOB} columns), a fixed-size record format is
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used. This is faster but unfortunately may waste some space.
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@xref{MyISAM table formats}.
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@xref{MyISAM table formats, , @code{MyISAM} table formats}.
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@item
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The primary index of a table should be as short as possible. This makes
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@ -27079,9 +27081,9 @@ MySQL is multi-threaded, so it may have many queries on the same table
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simultaneously. To minimise the problem with two threads having
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different states on the same file, the table is opened independently by
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each concurrent thread. This takes some memory but will normaly increase
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performance. Wth ISAM and MyISAM tables this also requires one extra file
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descriptor for the datafile. With these table types the index file
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descriptor is shared between all threads.
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performance. Wth @code{ISAM} and @code{MyISAM} tables this also requires
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one extra file descriptor for the datafile. With these table types the index
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file descriptor is shared between all threads.
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You can read more about this topic in the next section. @xref{Table cache}.
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@ -27114,7 +27116,7 @@ Make sure that your operating system can handle the number of open file
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descriptors implied by the @code{table_cache} setting. If
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@code{table_cache} is set too high, MySQL may run out of file
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descriptors and refuse connections, fail to perform queries, and be very
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unreliable. You also have to take into account that the MyISAM table
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unreliable. You also have to take into account that the @code{MyISAM} table
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handler needs two file descriptors for each unique open table. You can
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in increase the number of file descriptors available for MySQL with
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the @code{--open-files-limit=#} startup option. @xref{Not enough file
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@ -27139,7 +27141,7 @@ a thread is no longer using a table.
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When someone executes @code{mysqladmin refresh} or
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@code{mysqladmin flush-tables}.
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@item
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When someone executes 'FLUSH TABLES'
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When someone executes a @code{FLUSH TABLES} statement.
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@end itemize
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When the table cache fills up, the server uses the following procedure
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@ -27491,7 +27493,7 @@ threads on a single processor. With more load/CPUs the difference should
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get bigger.
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@item
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Running with @code{--log-bin} makes @strong{[MySQL} 1% slower.
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Running with @code{--log-bin} makes MySQL 1% slower.
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@item
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Compiling on Linux-x86 using gcc without frame pointers
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@ -27535,8 +27537,8 @@ a query is running, a copy of the current query string is also allocated.
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All threads share the same base memory.
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@item
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Only the compressed ISAM / MyISAM tables are memory mapped. This is
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because the 32-bit memory space of 4GB is not large enough for most
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Only the compressed @code{ISAM} / @code{MyISAM} tables are memory mapped. This
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is because the 32-bit memory space of 4GB is not large enough for most
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big tables. When systems with a 64-bit address space become more
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common we may add general support for memory mapping.
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@ -27551,20 +27553,20 @@ random-read buffer is allocated to avoid disk seeks.
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@item
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All joins are done in one pass, and most joins can be done without even
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using a temporary table. Most temporary tables are memory-based (HEAP)
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using a temporary table. Most temporary tables are memory-based (@code{HEAP})
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tables. Temporary tables with a big record length (calculated as the
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sum of all column lengths) or that contain @code{BLOB} columns are
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stored on disk.
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One problem in MySQL versions before Version 3.23.2 is that if a HEAP table
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exceeds the size of @code{tmp_table_size}, you get the error @code{The
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One problem in MySQL versions before Version 3.23.2 is that if a @code{HEAP}
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table exceeds the size of @code{tmp_table_size}, you get the error @code{The
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table tbl_name is full}. In newer versions this is handled by
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automatically changing the in-memory (HEAP) table to a disk-based
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(MyISAM) table as necessary. To work around this problem, you can
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automatically changing the in-memory (@code{HEAP}) table to a disk-based
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(@code{MyISAM}) table as necessary. To work around this problem, you can
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increase the temporary table size by setting the @code{tmp_table_size}
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option to @code{mysqld}, or by setting the SQL option
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@code{BIG_TABLES} in the client program. @xref{SET OPTION, ,
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@code{SET}}. In MySQL Version 3.20, the maximum size of the
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@code{SET} Syntax}. In MySQL Version 3.20, the maximum size of the
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temporary table was @code{record_buffer*16}, so if you are using this
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version, you have to increase the value of @code{record_buffer}. You can
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also start @code{mysqld} with the @code{--big-tables} option to always
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@ -33529,7 +33531,7 @@ The given @code{key_string} will be used to crypt @code{string_to_encrypt}.
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The return string will be a binary string where the first character
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will be @code{CHAR(128 | key_number)}.
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The 128 is added to make it easier to recognize an encrypted key.
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The 128 is added to make it easier to recognise an encrypted key.
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If you use a string key, @code{key_number} will be 127.
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On error, this function returns @code{NULL}.
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@ -39798,7 +39800,7 @@ Use less locking: if you can afford a @code{SELECT} to return
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data from an old snapshot, do not add the clause
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@code{FOR UPDATE} or @code{LOCK IN SHARE MODE} to it.
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@item
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If nothing helps, serialize your transactions with table level
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If nothing helps, serialise your transactions with table level
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locks: @code{LOCK TABLES t1 WRITE, t2 READ, ... ;
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[do something with tables t1 and t2 here]; UNLOCK TABLES.}
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Table level locks make you transactions to queue nicely,
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