Added documentation about GEMINI tables

2025-10-28 17:15:19 +03:00 · 2001-03-08 17:44:30 +02:00
parent cb3dfd8252
commit b947bc4aed
1 changed files with 146 additions and 34 deletions
--- a/Docs/manual.texi
+++ b/Docs/manual.texi
@@ -487,7 +487,8 @@ MySQL Table Types
 * ISAM::                        ISAM tables
 * HEAP::                        HEAP tables
 * BDB::                         BDB or Berkeley_db tables
-* INNOBASE::                    
+* GEMINI::                      GEMINI tables
+* INNOBASE::                    INNOBASE tables

 MyISAM Tables

@@ -509,11 +510,18 @@ BDB or Berkeley_db Tables
 * BDB TODO::                    
 * BDB errors::                  

+GEMINI tables
+
+* GEMINI overview::
+* GEMINI start::
+* GEMINI features::
+* GEMINI TODO::
+
 INNOBASE Tables

 * INNOBASE overview::           
-* Innobase startup options::    
-* Using Innobase tables::       
+* INNOBASE start::    
+* Using INNOBASE tables::       
 * INNOBASE restrictions::       

 MySQL Tutorial
@@ -582,7 +590,7 @@ Replication in MySQL
 * Replication Options::         Replication Options in my.cnf
 * Replication SQL::             SQL Commands related to replication
 * Replication FAQ::             Frequently Asked Questions about replication
-* Troubleshooting Replication:: Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.
+* Troubleshooting Replication:: Troubleshooting Replication

 Getting Maximum Performance from MySQL

@@ -4198,7 +4206,7 @@ Please report bad or out-of-date mirrors to @email{webmaster@@mysql.com}.
@c @uref{http://mysql.tradenet.ee, WWW}

@item
-@c EMAIL: tonu@spamm.ee (Tõnu Samuel)
+@c EMAIL: tonu@spam.ee (Tõnu Samuel)
@image{Flags/estonia} Estonia [OKinteractive] @
@uref{http://mysql.mirror.ok.ee, WWW}

@@ -9527,6 +9535,12 @@ problems. @xref{Windows}.
 If you are using BDB (Berkeley DB) tables, you should familiarize
 yourself with the different BDB specific startup options. @xref{BDB start}.

+If you are using Gemini tables, refer to the Gemini-specific startup options.
+@xref{GEMINI start}.
+
+If you are using Innobase tables, refer to the Innobase-specific startup
+options. @xref{INNOBASE start}.
+
@node Automatic start, Command-line options, Starting server, Post-installation
@subsection Starting and Stopping MySQL Automatically
@cindex starting, the server automatically
@@ -10911,9 +10925,10 @@ Many of our users who have speed foremost in their minds are not at all
 concerned about transactions. For them transactions are not an
 issue. For those of our users who are concerned with or have wondered
 about transactions vis-a-vis @strong{MySQL}, there is a ``@strong{MySQL}
-way'' as we have outlined above.  For those where safety is more important
-than speed, we recommend them to use the @code{BDB} tables for all their
-critical data. @xref{BDB}.
+way'' as we have outlined above.  For those where safety is more
+important than speed, we recommend them to use the @code{BDB},
+@code{GEMINI} or @code{INNOBASE} tables for all their critical
+data. @xref{Table types}.

 One final note: We are currently working on a safe replication schema
 that we believe to be better than any commercial replication system we
@@ -11139,12 +11154,14 @@ Entry level SQL92. ODBC levels 0-2.
@cindex tables, updating
@cindex updating, tables
@cindex @code{BDB} tables
-
+@cindex @code{GEMINI} tables
+@cindex @code{INNOBASE} tables

 The following mostly applies only for @code{ISAM}, @code{MyISAM}, and
-@code{HEAP} tables. If you only use transaction-safe tables (@code{BDB}
-tables) in an a update, you can do @code{COMMIT} and @code{ROLLBACK} also
-with @strong{MySQL}.  @xref{COMMIT}.
+@code{HEAP} tables. If you only use transaction-safe tables (@code{BDB},
+@code{GEMINI} or @code{INNOBASE} tables) in an a update, you can do
+@code{COMMIT} and @code{ROLLBACK} also with @strong{MySQL}.
+@xref{COMMIT}.

 The problem with handling @code{COMMIT}-@code{ROLLBACK} efficiently with
 the above table types would require a completely different table layout
@@ -18339,6 +18356,7 @@ The different table types are:

@multitable @columnfractions .20 .80
@item BDB or Berkeley_db @tab Transaction-safe tables with page locking. @xref{BDB}.
+@item GEMINI @tab Transaction-safe tables with row-level locking @xref{GEMINI}.
@item HEAP @tab The data for this table is only stored in memory. @xref{HEAP}.
@item ISAM @tab The original table handler. @xref{ISAM}.
@item INNOBASE @tab Transaction-safe tables with row locking. @xref{INNOBASE}.
@@ -22608,6 +22626,7 @@ used them.
@cindex table types, choosing
@cindex @code{BDB} table type
@cindex @code{Berkeley_db} table type
+@cindex @code{GEMINI} table type
@cindex @code{HEAP} table type
@cindex @code{ISAM} table type
@cindex @code{INNOBASE} table type
@@ -22678,7 +22697,8 @@ of both worlds.
 * ISAM::                        ISAM tables
 * HEAP::                        HEAP tables
 * BDB::                         BDB or Berkeley_db tables
-* INNOBASE::                    
+* GEMINI::                      GEMINI tables
+* INNOBASE::                    INNOBASE tables
@end menu

@node MyISAM, MERGE, Table types, Table types
@@ -23295,7 +23315,7 @@ SUM_OVER_ALL_KEYS(max_length_of_key + sizeof(char*) * 2)

@cindex tables, @code{BDB}
@cindex tables, @code{Berkeley DB}
-@node BDB, INNOBASE, HEAP, Table types
+@node BDB, GEMINI, HEAP, Table types
@section BDB or Berkeley_db Tables

@menu
@@ -23310,9 +23330,8 @@ SUM_OVER_ALL_KEYS(max_length_of_key + sizeof(char*) * 2)
@node BDB overview, BDB install, BDB, BDB
@subsection Overview over BDB tables

-BDB tables are included in the @strong{MySQL} source distribution
-starting from 3.23.34 and will be activated in the @strong{MySQL}-max
-binary.
+BDB is included in the @strong{MySQL} source distribution starting
+from 3.23.34 and will be activated in the @strong{MySQL}-max binary.

 Berkeley DB (@uref{http://www.sleepycat.com}) has provided
@strong{MySQL} with a transaction-safe table handler. This will survive
@@ -23509,22 +23528,103 @@ This is not fatal but we don't recommend that you delete tables if you are
 not in @code{auto_commit} mode, until this problem is fixed (the fix is
 not trivial).

-@node INNOBASE,  , BDB, Table types
+@cindex tables, @code{GEMINI}
+@node GEMINI, INNOBASE, BDB, Table types
+@section GEMINI Tables
+
+@menu
+* GEMINI overview::
+* GEMINI start::
+* GEMINI features::
+* GEMINI TODO::
+@end menu
+
+@node GEMINI overview, GEMINI start, GEMINI, GEMINI
+@subsection Overview of GEMINI tables
+
+The @code{GEMINI} table type is developed and supported by NuSphere Corporation
+(@uref{http://www.nusphere.com}).  It features row-level locking, transaction
+support (@code{COMMIT} and @code{ROLLBACK}), and automatic crash recovery.
+
+@code{GEMINI} tables will be included in the @strong{MySQL} 4.0 source
+distribution.
+
+@node GEMINI start, GEMINI features, GEMINI overview, GEMINI
+@subsection GEMINI startup options
+
+If you are running with @code{AUTOCOMMIT=0} then your changes in @code{GEMINI}
+tables will not be updated until you execute @code{COMMIT}.  Instead of commit
+you can execute @code{ROLLBACK} to forget your changes. @xref{COMMIT}.
+
+If you are running with @code{AUTOCOMMIT=1} (the default), your changes
+will be committed immediately.  You can start an extended transaction with
+the @code{BEGIN WORK} SQL command, after which your changes will not be
+committed until you execute @code{COMMIT} (or decide to @code{ROLLBACK}
+the changes).
+
+The following options to @code{mysqld} can be used to change the behavior of
+GEMINI tables:
+
+@multitable @columnfractions .30 .70
+@item @strong{Option} @tab @strong{Meaning}
+@item @code{--gemini-full-recovery} @tab Default.
+@item @code{--gemini-no-recovery} @tab Turn off recovery logging.  Not recommended.
+@item @code{--gemini-lazy-commit} @tab Relaxes the flush log at commit rule.
+@item @code{--gemini-unbuffered-io} @tab All database writes bypass OS cache.
+@item @code{--skip-gemini} @tab Don't use Gemini.
+@item @code{--O gemini_db_buffers=#} @tab Number of database buffers in database cache.
+@item @code{--O gemini_connection_limit=#} @tab Maximum number of connections to Gemini.
+@item @code{--O gemini_spin_retries=#} @tab Spin lock retries (optimization).
+@item @code{--O gemini_io_threads=#} @tab Number of background I/O threads.
+@item @code{--O gemini_lock_table_size=#} @tab Set the maximum number of locks.  Default 4096.
+@end multitable
+
+If you use @code{--skip-gemini}, @strong{MySQL} will not initialize the
+Gemini table handler, saving memory; you cannot use Gemini tables if you
+use @code{--skip-gemini}.
+
+@node GEMINI features, GEMINI TODO, GEMINI start, GEMINI
+@subsection Features of @code{GEMINI} tables:
+
+@itemize @bullet
+@item
+If a query result can be resolved solely from the index key, Gemini will
+not read the actual row stored in the database.
+@item
+Locking on Gemini tables is done at row level.
+@item
+@code{SELECT COUNT(*) FROM table_name} is fast; Gemini maintains a count
+of the number of rows in the table.
+@end itemize
+
+@node GEMINI TODO,  , GEMINI features, GEMINI
+@subsection Current limitations of @code{GEMINI} tables:
+
+@itemize @bullet
+@item
+BLOB columns are not supported in @code{GEMINI} tables.
+@item
+The maximum number of concurrent users accessing @code{GEMINI} tables is
+limited by @code{gemini_connection_limit}.  The default is 100 users.
+@end itemize
+
+NuSphere is working on removing these limitations.
+
+@node INNOBASE,  , GEMINI, Table types
@section INNOBASE Tables

@menu
 * INNOBASE overview::           
-* Innobase startup options::    
-* Using Innobase tables::       
-* INNOBASE restrictions::       
+* INNOBASE start::              INNOBASE startup options
+* Using INNOBASE tables::       Using INNOBASE tables
+* INNOBASE restrictions::       Some restrictions on @code{INNOBASE} tables:
@end menu

-@node INNOBASE overview, Innobase startup options, INNOBASE, INNOBASE
+@node INNOBASE overview, INNOBASE start, INNOBASE, INNOBASE
@subsection INNOBASE Tables overview

-Innobase tables are included in the @strong{MySQL} source distribution
-starting from 3.23.34 and will be activated in the @strong{MySQL}-max
-binary.
+Innobase is included in the @strong{MySQL} source distribution starting
+from 3.23.34 and will be activated in the @strong{MySQL}-max binary.

 If you have downloaded a binary version of @strong{MySQL} that includes
 support for Berkeley DB, simply follow the instructions for
@@ -23550,8 +23650,8 @@ Innobase is a table handler that is under the GNU GPL License Version 2
 (of June 1991). In the source distribution of MySQL, Innobase appears as
 a subdirectory.

-@node Innobase startup options, Using Innobase tables, INNOBASE overview, INNOBASE
-@subsection Innobase startup options
+@node INNOBASE start, Using INNOBASE tables, INNOBASE overview, INNOBASE
+@subsection INNOBASE startup options

 To use Innobase tables you must specify configuration parameters
 in the MySQL configuration file in the @code{[mysqld]} section of
@@ -23647,8 +23747,8 @@ Innobase cannot notice. In cases like this the timeout is useful to
 resolve the situation.
@end multitable

-@node Using Innobase tables, INNOBASE restrictions, Innobase startup options, INNOBASE
-@subsection Using Innobase tables
+@node Using INNOBASE tables, INNOBASE restrictions, INNOBASE start, INNOBASE
+@subsection Using INNOBASE tables

 Technically, Innobase is a database backend placed under MySQL. Innobase
 has its own buffer pool for caching data and indexes in main
@@ -23721,7 +23821,7 @@ P.O.Box 800
 Finland
@end example

-@node INNOBASE restrictions,  , Using Innobase tables, INNOBASE
+@node INNOBASE restrictions,  , Using INNOBASE tables, INNOBASE
@subsection Some restrictions on @code{INNOBASE} tables:

@itemize @bullet
@@ -26472,7 +26572,7 @@ tables}.
 * Replication Options::         Replication Options in my.cnf
 * Replication SQL::             SQL Commands related to replication
 * Replication FAQ::             Frequently Asked Questions about replication
-* Troubleshooting Replication:: Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.  Troubleshooting Replication.
+* Troubleshooting Replication:: Troubleshooting Replication
@end menu

@node Replication Intro, Replication Implementation, Replication, Replication
@@ -29911,7 +30011,7 @@ performance in a threaded system!

@xref{Multiple servers}.

-This is an example of the config file on behalf of @code{mysqld_multi}. 
+This is an example of the config file on behalf of @code{mysqld_multi}.

@example
 # This file should probably be in your home dir (~/.my.cnf) or /etc/my.cnf
@@ -39136,8 +39236,7 @@ Two APIs are available in the @strong{MySQL}
@section MySQL Python APIs

 The @strong{MySQL} @uref{http://www.mysql.com/Downloads/Contrib/,Contrib directory}
-contains a Python
-interface written by Joseph Skinner.
+contains a Python interface written by Joseph Skinner.

 You can also use the Python interface to iODBC to access a
@strong{MySQL} server.
@@ -41447,6 +41546,12 @@ Our security expert.
@item
 Vio interface (foundation for the the encrypted client/server protocol).
@item
+MySQL Filesystem (Way to use MySQL databases as files and directories).
+@item
+CASE Expression 
+@item
+MD5(), COALESCE()  functions.
+@item
@code{RAID} support for @code{MyISAM} tables.
@end itemize

@@ -41902,6 +42007,8 @@ not yet 100 % confident in this code.
 Added the @code{INNOBASE} table handler and the @code{BDB} table handler
 to the @strong{MySQL} source distribution.
@item
+Updated the documentation about @code{GEMINI} tables.
+@item
@code{REPLACE} will not replace a row that conflicts with an
@code{auto_increment} generated key.
@item
@@ -46804,6 +46911,11 @@ ORDER BY columns in the result, something that is you are not allowed
 to do in ANSI SQL.

@item
+Because @strong{MySQL} allows you to work with table types that doesn't
+support transactions (and thus can't @code{rollback} data) some things
+behaves a little different in @strong{MySQL} than in other SQL servers:
+(This is just to ensure that @strong{MySQL} never need to do a rollback
+for a SQL command).  This may be a little akward at times as column
 Because @strong{MySQL} allows you to work with table types that don't
 support transactions, and thus can't @code{rollback} data, some things
 behave a little differently in @strong{MySQL} than in other SQL servers.