Provided by: mysql-utilities_1.3.5-2_all bug

NAME

       mysqldiff - Identify Differences Among Database Objects

SYNOPSIS

       mysqldiff [options] {db1[:db1] | {db1.obj1[:db2.obj2]} ...

DESCRIPTION

       This utility reads the definitions of objects and compares them using a diff-like method
       to determine whether they are the same. The utility displays the differences for objects
       that are not the same.

       Use the notation db1:db2 to name two databases to compare, or, alternatively just db1 to
       compare two databases with the same name. The latter case is a convenience notation for
       comparing same-named databases on different servers.

       The comparison may be run against two databases of different names on a single server by
       specifying only the --server1 option. The user can also connect to another server by
       specifying the --server2 option. In this case, db1 is taken from server1 and db2 from
       server2.

       When a database pair is specified, all objects in one database are compared to the
       corresponding objects in the other. Any objects not appearing in either database produce
       an error.

       To compare a specific pair of objects, add an object name to each database name in db.obj
       format. For example, use db1.obj1:db2.obj2 to compare two named objects, or db1.obj1 to
       compare an object with the same name in databases with the same name. It is not legal to
       mix a database name with an object name. For example, db1.obj1:db2 and db1:db2.obj2 are
       illegal.

       The comparison may be run against a single server for comparing two databases of different
       names on the same server by specifying only the --server1 option. Alternatively, you can
       also connect to another server by specifying the --server2 option. In this case, the first
       object to compare is taken from server1 and the second from server2.

       By default, the utility generates object differences as a difference report. However, you
       can generate a transformation report containing SQL statements for transforming the
       objects for conformity instead. Use the 'sql' value for the --difftype option to produce a
       listing that contains the appropriate ALTER commands to conform the object definitions for
       the object pairs specified. If a transformation cannot be formed, the utility reports the
       diff of the object along with a warning statement. See important limitations in the NOTES
       section.

       To specify how to display diff-style output, use one of the following values with the
       --difftype option:

       •   unified (default)

           Display unified format output.

       •   context

           Display context format output.

       •   differ

           Display differ-style format output.

       •   sql

           Display SQL transformation statement output.

       The --changes-for option controls the direction of the difference (by specifying the
       object to be transformed) in either the difference report (default) or the transformation
       report (designated with the --difftype=sql option). Consider the following command:

           mysqldiff --server1=root@host1 --server2=root@host2 --difftype=sql \
             db1.table1:dbx.table3

       The leftmost database (db1) exists on the server designated by the --server1 option
       (host1). The rightmost database (dbx) exists on the server designated by the --server2
       option (host2).

       •   --changes-for=server1: Produce output that shows how to make the definitions of
           objects on server1 like the definitions of the corresponding objects on server2.

       •   --changes-for=server2: Produce output that shows how to make the definitions of
           objects on server2 like the definitions of the corresponding objects on server1.

       The default direction is server1.

       For sql difference format, you can also see the reverse transformation by specifying the
       --show-reverse option.

       The utility stops on the first occurrence of missing objects or when an object does not
       match. To override this behavior, specify the --force option to cause the utility to
       attempt to compare all objects listed as arguments.
             OPTIONS

       mysqldiff accepts the following command-line options:

       •   --help

           Display a help message and exit.

       •   --changes-for=<direction>

           Specify the server to show transformations to match the other server. For example, to
           see the transformation for transforming object definitions on server1 to match the
           corresponding definitions on server2, use --changes-for=server1. Permitted values are
           server1 and server2. The default is server1.

       •   --difftype=<difftype>, -d<difftype>

           Specify the difference display format. Permitted format values are unified, context,
           differ, and sql. The default is unified.

       •   --force

           Do not halt at the first difference found. Process all objects to find all
           differences.

       •   --quiet, -q

           Do not print anything. Return only an exit code of success or failure.

       •   --server1=<source>

           Connection information for the first server in the format:
           <user>[:<passwd>]@<host>[:<port>][:<socket>] or <login-path>[:<port>][:<socket>].

       •   --server2=<source>

           Connection information for the second server in the format:
           <user>[:<passwd>]@<host>[:<port>][:<socket>] or <login-path>[:<port>][:<socket>].

       •   --show-reverse

           Produce a transformation report containing the SQL statements to conform the object
           definitions specified in reverse. For example, if --changes-for is set to server1,
           also generate the transformation for server2. Note: The reverse changes are annotated
           and marked as comments.

       •   --verbose, -v

           Specify how much information to display. Use this option multiple times to increase
           the amount of information. For example, -v = verbose, -vv = more verbose, -vvv =
           debug.

       •   --version

           Display version information and exit.

       •   --width=<number>

           Change the display width of the test report. The default is 75 characters.
             NOTES

       You must provide connection parameters (user, host, password, and so forth) for an account
       that has the appropriate privileges to access all objects to be compared.

       The SQL transformation feature has these known limitations:

       •   When tables with partition differences are encountered, the utility generates the
           ALTER TABLE statement for all other changes but prints a warning and omits the
           partition differences.

       •   If the transformation detects table options in the source table (specified with the
           --changes-for option) that are not changed or do not exist in the target table, the
           utility generates the ALTER TABLE statement for all other changes but prints a warning
           and omits the table option differences.

       •   Rename for events is not supported. This is because mysqldiff compares objects by
           name. In this case, depending on the direction of the diff, the event is identified as
           needing to be added or a DROP EVENT statement is generated.

       •   Changes in the definer clause for events are not supported.

       •   SQL extensions specific to MySQL Cluster are not supported.

       For the --difftype option, the permitted values are not case sensitive. In addition,
       values may be specified as any unambiguous prefix of a valid value. For example,
       --difftype=d specifies the differ type. An error occurs if a prefix matches more than one
       valid value.

       The path to the MySQL client tools should be included in the PATH environment variable in
       order to use the authentication mechanism with login-paths. This will allow the utility to
       use the my_print_defaults tools which is required to read the login-path values from the
       login configuration file (.mylogin.cnf).

       If any database object identifier specified as an argument contains special characters or
       is a reserved word, then it must be appropriately quoted with backticks (`). In turn,
       names quoted with backticks must also be quoted with single or double quotes depending on
       the operating system, i.e. (") in Windows or (') in non-Windows systems, in order for the
       utilities to read backtick quoted identifiers as a single argument. For example, to show
       the difference between table weird`table1 from database weird`db.name and table
       weird`table2 from database other:weird`db.name, the objects pair must be specified using
       the following syntax (in non-Windows):
       '`weird``db.name`.`weird``table1`:`other:weird``db.name`.`weird``table2`'.
             EXAMPLES

       To compare the employees and emp databases on the local server, use this command:

           $ mysqldiff --server1=root@localhost employees:emp1
           # server1 on localhost: ... connected.
           WARNING: Objects in server1:employees but not in server2:emp1:
             EVENT: e1
           Compare failed. One or more differences found.
           $ mysqldiff --server1=root@localhost \
                      employees.t1:emp1.t1 employees.t3:emp1.t3
           # server1 on localhost: ... connected.
           # Comparing employees.t1 to emp1.t1                                [PASS]
           # server1 on localhost: ... connected.
           # Comparing employees.t3 to emp1.t3                                [PASS]
           Success. All objects are the same.
           $ mysqldiff --server1=root@localhost \
                    employees.salaries:emp1.salaries --differ
           # server1 on localhost: ... connected.
           # Comparing employees.salaries to emp1.salaries                    [FAIL]
           # Object definitions are not the same:
             CREATE TABLE `salaries` (
               `emp_no` int(11) NOT NULL,
               `salary` int(11) NOT NULL,
               `from_date` date NOT NULL,
               `to_date` date NOT NULL,
               PRIMARY KEY (`emp_no`,`from_date`),
               KEY `emp_no` (`emp_no`)
           - ) ENGINE=InnoDB DEFAULT CHARSET=latin1
           ?           ^^^^^
           + ) ENGINE=MyISAM DEFAULT CHARSET=latin1
           ?          ++ ^^^
           Compare failed. One or more differences found.

       The following examples show how to generate a transformation report. Assume the following
       object definitions:

       Host1:

           CREATE TABLE db1.table1 (num int, misc char(30));

       Host2:

           CREATE TABLE dbx.table3 (num int, notes char(30), misc char(55));

       To generate a set of SQL statements that transform the definition of db1.table1 to
       dbx.table3, use this command:

           $ mysqldiff --server1=root@host1 --server2=root@host2 \
                 --changes-for=server1 --difftype=sql \
                 db1.table1:dbx.table3
           # server1 on host1: ... connected.
           # server2 on host2: ... connected.
           # Comparing db1.table1 to dbx.table3                               [FAIL]
           # Transformation statements:
           ALTER TABLE db1.table1
             ADD COLUMN notes char(30) AFTER a,
             CHANGE COLUMN misc misc char(55);
           Compare failed. One or more differences found.

       To generate a set of SQL statements that transform the definition of dbx.table3 to
       db1.table1, use this command:

           $ mysqldiff --server1=root@host1 --server2=root@host2 \
                 --changes-for=server2 --difftype=sql \
                 db1.table1:dbx.table3
           # server1 on host1: ... connected.
           # server2 on host2: ... connected.
           # Comparing db1.table1 to dbx.table3                               [FAIL]
           # Transformation statements:
           ALTER TABLE dbx.table3
             DROP COLUMN notes,
             CHANGE COLUMN misc misc char(30);
           Compare failed. One or more differences found.

       To generate a set of SQL statements that transform the definitions of dbx.table3 and
       db1.table1 in both directions, use this command:

           $ mysqldiff --server1=root@host1 --server2=root@host2 \
                 --show-reverse --difftype=sql \
                 db1.table1:dbx.table3
           # server1 on host1: ... connected.
           # server2 on host2: ... connected.
           # Comparing db1.table1 to dbx.table3                               [FAIL]
           # Transformation statements:
           # --destination=server1:
           ALTER TABLE db1.table1
             ADD COLUMN notes char(30) AFTER a,
             CHANGE COLUMN misc misc char(55);
           # --destination=server2:
           # ALTER TABLE dbx.table3
           #   DROP COLUMN notes,
           #   CHANGE COLUMN misc misc char(30);
           Compare failed. One or more differences found.

COPYRIGHT

SEE ALSO

       For more information, please refer to the MySQL Utilities section of the MySQL Workbench
       Reference Manual, which is available online at http://dev.mysql.com/doc/workbench/en/.

AUTHOR

       Oracle Corporation (http://dev.mysql.com/).