bulk insert optimization documented

or  INSERT [LOW_PRIORITY | DELAYED] [IGNORE]

        [INTO] tbl_name

        SET col_name=expression, col_name=expression, ...

or  INSERT [LOW_PRIORITY] [IGNORE] [INTO] tbl_name

        SELECT ...

@end example

differ somewhat:

@example

+-------------------------+---------------------------+

+------------------------------+---------------------------+

| Variable_name                | Value                     |

+-------------------------+---------------------------+

+------------------------------+---------------------------+

| ansi_mode                    | OFF                       |

| back_log                     | 50                        |

| basedir                      | /my/monty/                |

| max_sort_length              | 1024                      |

| max_tmp_tables               | 32                        |

| max_write_lock_count         | 4294967295                |

| myisam_bulk_insert_tree_size | 8388608                   |

| myisam_recover_options       | DEFAULT                   |

| myisam_sort_buffer_size      | 8388608                   |

| net_buffer_length            | 16384                     |

| tmpdir                       | /tmp/                     |

| version                      | 3.23.29a-gamma-debug      |

| wait_timeout                 | 28800                     |

+-------------------------+---------------------------+

+------------------------------+---------------------------+

@end example

Each option is described below. Values for buffer sizes, lengths, and stack

@code{REPAIR} or when creating indexes with @code{CREATE INDEX} or

@code{ALTER TABLE}.

@item @code{myisam_bulk_insert_tree_size}

@strong{MySQL} uses special tree-like cache to make bulk inserts (that is,

@code{INSERT ... SELECT},

@code{INSERT ... VALUES (...), (...), ...}, and

@code{LOAD DATA INFILE}) faster. This variable limits

the size of the cache tree in bytes @strong{per thread, per index}.

Default value is 8 MB.

@item @code{myisam_max_extra_sort_file_size}.

If the creating of the temporary file for fast index creation would be

this much bigger than using the key cache, then prefer the key cache

@item @code{-O myisam_sort_buffer_size=#} @tab Buffer used when recovering tables.

@item @code{--delay-key-write-for-all-tables} @tab Don't flush key buffers between writes for any MyISAM table

@item @code{-O myisam_max_extra_sort_file_size=#} @tab Used to help @strong{MySQL} to decide when to use the slow but safe key cache index create method. @strong{NOTE} that this parameter is given in megabytes!

@item @code{-O myisam_max_sort_file_size=#} @tab Don't use the fast sort index method to created index if the temporary file would get bigger than this.

@strong{NOTE} that this paramter is given in megabytes!

@item @code{-O myisam_max_sort_file_size=#} @tab Don't use the fast sort index method to created index if the temporary file would get bigger than this. @strong{NOTE} that this paramter is given in megabytes!

@item @code{-O myisam_bulk_insert_tree_size=#} @tab Size of tree cache used in bulk insert optimization. @strong{NOTE} that this is a limit @strong{per index}!

@end multitable

The automatic recovery is activated if you start @code{mysqld} with

If you are inserting many rows from the same client at the same time, use

multiple value lists @code{INSERT} statements. This is much faster (many

times in some cases) than using separate @code{INSERT} statements.

Tune up @code{myisam_bulk_insert_tree_size} variable to make it even

faster. @xref{SHOW VARIABLES}.

@item

If you are inserting a lot of rows from different clients, you can get

higher speed by using the @code{INSERT DELAYED} statement. @xref{INSERT,

@itemize @bullet

@item

Tree-like cache to speed up bulk inserts and

@code{myisam_bulk_insert_tree_size} variable.

@item

Added @code{ALTER TABLE table_name DISABLE KEYS} and

      @code{ALTER TABLE table_name ENABLE KEYS} commands.

@item

  if (remove_colour == BLACK)

    rb_delete_fixup(tree,parent);

  if (tree->free)

    (*tree->free)(ELEMENT_KEY(tree,element));

    (*tree->free)(ELEMENT_KEY(tree,element), free_free, tree->custom_arg);

  my_free((gptr) element,MYF(0));

  tree->elements_in_tree--;

  return 0;