Commit 5883ec2c authored by monty@donna.mysql.com's avatar monty@donna.mysql.com

Small manual changes + fix bug in range optimizer becasue of commented code

parent 53d7c306
......@@ -17654,13 +17654,14 @@ This will create a @code{HEAP} table with 3 columns. Note that the table will
automatically be deleted if any errors occur while copying data
into the table.
@item
The @code{RAID_TYPE} option will help you to break the 2G/4G limit on
Operating Systems that don't support big files. You can get also more speed
from the I/O bottleneck by putting @code{RAID} directories on different
physical disks. @code{RAID_TYPE} will work on any OS, as long as you have
configured @strong{MySQL} with @code{--with-raid}. For now the only allowed
@code{RAID_TYPE} is @code{STRIPED} (@code{1} and @code{RAID0} are aliases
for this).
The @code{RAID_TYPE} option will help you to break the 2G/4G limit for
the MyISAM data file (not the index file) onOperating Systems that don't
support big files. You can get also more speed from the I/O bottleneck
by putting @code{RAID} directories on different physical
disks. @code{RAID_TYPE} will work on any OS, as long as you have
configured @strong{MySQL} with @code{--with-raid}. For now the only
allowed @code{RAID_TYPE} is @code{STRIPED} (@code{1} and @code{RAID0}
are aliases for this).
If you specify @code{RAID_TYPE=STRIPED} for a @code{MyISAM} table,
@code{MyISAM} will create @code{RAID_CHUNKS} subdirectories named 00,
......@@ -17669,7 +17670,7 @@ If you specify @code{RAID_TYPE=STRIPED} for a @code{MyISAM} table,
to the data file, the @code{RAID} handler will map the first
@code{RAID_CHUNKSIZE} *1024 bytes to the first file, the next
@code{RAID_CHUNKSIZE} *1024 bytes to the next file and so on.
@item
@code{UNION} is used when you want to use a collection of identical
tables as one. This only works with MERGE tables. @xref{MERGE}.
......@@ -20817,10 +20818,11 @@ LOCK TABLES tbl_name [AS alias] @{READ | [READ LOCAL] | [LOW_PRIORITY] WRITE@}
UNLOCK TABLES
@end example
@code{LOCK TABLES} locks tables for the current thread. @code{UNLOCK TABLES}
releases any locks held by the current thread. All tables that are locked by
the current thread are automatically unlocked when the thread issues another
@code{LOCK TABLES}, or when the connection to the server is closed.
@code{LOCK TABLES} locks tables for the current thread. @code{UNLOCK
TABLES} releases any locks held by the current thread. All tables that
are locked by the current thread are automatically unlocked when the
thread issues another @code{LOCK TABLES}, or when the connection to the
server is closed.
If a thread obtains a @code{READ} lock on a table, that thread (and all other
threads) can only read from the table. If a thread obtains a @code{WRITE}
......@@ -20847,10 +20849,11 @@ use @code{LOW_PRIORITY WRITE} locks if you are sure that there will
eventually be a time when no threads will have a @code{READ} lock.
When you use @code{LOCK TABLES}, you must lock all tables that you are
going to use and you must use the same alias that you are going to use in
your queries! If you are using a table multiple times in a query (with
aliases), you must get a lock for each alias! This policy ensures that
table locking is deadlock free.
going to use and you must use the same alias that you are going to use
in your queries! If you are using a table multiple times in a query
(with aliases), you must get a lock for each alias! This policy ensures
that table locking is deadlock free andh makes the locking code smaller,
simpler and much faster.
Note that you should @strong{NOT} lock any tables that you are using with
@code{INSERT DELAYED}. This is because that in this case the @code{INSERT}
......@@ -393,7 +393,7 @@ QUICK_SELECT::QUICK_SELECT(TABLE *table,uint key_nr,bool no_alloc)
else
bzero((char*) &alloc,sizeof(alloc));
file=head->file;
// error=file->index_init(index);
error=file->index_init(index);
record=head->record[0];
}
......
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