MYSQLDBCOMPARE(1)               MySQL Utilities              MYSQLDBCOMPARE(1)



NAME
       mysqldbcompare - Compare Two Databases and Identify Differences

SYNOPSIS
       mysqldbcompare [options] db1 [:db2] ...

DESCRIPTION
       This utility compares the objects and data from two databases to find
       differences. It identifies objects having different definitions in the
       two databases and presents them in a diff-style format of choice.
       Differences in the data are shown using a similar diff-style format.
       Changed or missing rows are shown in a standard format of GRID, CSV,
       TAB, or VERTICAL.

       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.

       All databases between two servers can also be compared using the --all
       option. In this case, only the databases in common (with the same name)
       between the servers are successively compared. Therefore, no databases
       need to be specified but the --server1 and --server2 options are
       required. Users can skip the comparison of some of the databases using
       the --exclude option.

           Note
           The data must not be changed during the comparison. Unexpected
           errors may occur if data is changed during the comparison.

       The objects considered in the database include tables, views, triggers,
       procedures, functions, and events. A count for each object type can be
       shown with the -vv option.

       The check is performed using a series of steps called tests. By
       default, the utility stops on the first failed test, but you can
       specify the --run-all-tests option to cause the utility to run all
       tests regardless of their end state.

           Note
           Using --run-all-tests may produce expected cascade failures. For
           example, if the row counts differ among two tables being compared,
           the data consistency will also fail.

       The tests include the following:

        1. Check database definitions

           A database existence precondition check ensures that both databases
           exist. If they do not, no further processing is possible and the
           --run-all-tests option is ignored.

        2. Check existence of objects in both databases

           The test for objects in both databases identifies those objects
           missing from one or another database. The remaining tests apply
           only to those objects that appear in both databases. To skip this
           test, use the --skip-object-compare option. That can be useful when
           there are known missing objects among the databases.

        3. Compare object definitions

           The definitions (the CREATE statements) are compared and
           differences are presented. To skip this test, use the --skip-diff
           option. That can be useful when there are object name differences
           only that you want to ignore.

        4. Check table row counts

           This check ensures that both tables have the same number of rows.
           This does not ensure that the table data is consistent. It is
           merely a cursory check to indicate possible missing rows in one
           table or the other. The data consistency check identifies the
           missing rows. To skip this test, use the --skip-row-count option.

        5. Check table data consistency

           This check identifies both changed rows as well as missing rows
           from one or another of the tables in the databases. Changed rows
           are displayed as a diff-style report with the format chosen (GRID
           by default) and missing rows are also displayed using the format
           chosen. This check is divided in two steps: first the full table
           checksum is compared between the tables, then if this step fails
           (or is skipped) the algorithm to find rows differences is executed.
           To skip the preliminary checksum table step in this test, use the
           --skip-checksum-table option. To skip this full test, use the
           --skip-data-check option.

       You may want to use the --skip-xxx options to run only one of the
       tests. This might be helpful when working to bring two databases into
       synchronization, to avoid running all of the tests repeatedly during
       the process.

       Each test completes with one of the following states:

       o   pass

           The test succeeded.

       o   FAIL

           The test failed. Errors are displayed following the test state
           line.

       o   SKIP

           The test was skipped due to a missing prerequisite or a skip
           option.

       o   WARN

           The test encountered an unusual but not fatal error.

       o   -

           The test is not applicable to this object.

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

       o   unified (default)

           Display unified format output.

       o   context

           Display context format output.

       o   differ

           Display differ-style format output.

       o   sql

           Display SQL transformation statement output.

       To specify how to display output for changed or missing rows, use one
       of the following values with the --format option:

       o   grid (default)

           Display output in grid or table format like that of the mysql
           client command-line tool.

       o   csv

           Display output in comma-separated values format.

       o   tab

           Display output in tab-separated format.

       o   vertical

           Display output in single-column format like that of the \G command
           for the mysql client command-line tool.

       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:

           shell> mysqldbcompare --server1=root@host1 --server2=root@host2 --difftype=sql db1:dbx

       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).

       o   --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.

       o   --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.

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

       If the utility is to be run on a server that has binary logging
       enabled, and you do not want the comparison steps logged, use the
       --disable-binary-logging option.  OPTIONS.PP mysqldbcompare accepts the
       following command-line options:

       o   --all, -a

           Compare all database in common (with the same name) between two
           servers.

           The --all option ignores the following databases:
           INFORMATION_SCHEMA, PERFORMANCE_SCHEMA, mysql, and sys.

               Note
               The sys database is ignored as of Utilities 1.5.5.

       o   --help

           Display a help message and exit.

       o   --license

           Display license information and exit.

       o   --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.

       o   --character-set=<charset>

           Sets the client character set. The default is retrieved from the
           server variable character_set_client.

       o   --difftype=<difftype>, -d<difftype>

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

       o   --disable-binary-logging

           If binary logging is enabled, disable it during the operation to
           prevent comparison operations from being written to the binary log.
           Note: Disabling binary logging requires the SUPER privilege.

       o   --exclude=<exclude>, -x<exclude>

           Exclude one or more databases from the operation using either a
           specific name such as db1 or a search pattern. Use this option
           multiple times to specify multiple exclusions. By default, patterns
           use database patterns such as LIKE. With the --regexp option,
           patterns use regular expressions for matching names.

           Added in release-1.4.0.

       o   --format=<format>, -f<format>

           Specify the display format for changed or missing rows. Permitted
           format values are grid, csv, tab, and vertical. The default is
           grid.

       o   --compact

           Compacts the output by reducing the number of control lines that
           are displayed in the diff results. This option should be used
           together with one of the following difference types: unified or
           context. It is most effective when used with the unified difference
           type and the grid format.

       o   --quiet, -q

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

       o   --regexp, --basic-regexp, -G

           Perform pattern matches using the REGEXP operator. The default is
           to use LIKE for matching.

           Added in release-1.4.0.

       o   --run-all-tests, -t

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

       o   --server1=<source>

           Connection information for the first server.

           To connect to a server, it is necessary to specify connection
           parameters such as user name, host name, password, and either a
           port or socket. MySQL Utilities provides a number of ways to
           provide this information. All of the methods require specifying
           your choice via a command-line option such as --server, --master,
           --slave, etc. The methods include the following in order of most
           secure to least secure.

           o   Use login-paths from your .mylogin.cnf file (encrypted, not
               visible). Example : <login-path>[:<port>][:<socket>]

           o   Use a configuration file (unencrypted, not visible) Note:
               available in release-1.5.0. Example :
               <configuration-file-path>[:<section>]

           o   Specify the data on the command-line (unencrypted, visible).
               Example : <user>[:<passwd>]@<host>[:<port>][:<socket>]


       o   --server2=<source>

           Connection information for the second server.

           To connect to a server, it is necessary to specify connection
           parameters such as user name, host name, password, and either a
           port or socket. MySQL Utilities provides a number of ways to
           provide this information. All of the methods require specifying
           your choice via a command-line option such as --server, --master,
           --slave, etc. The methods include the following in order of most
           secure to least secure.

           o   Use login-paths from your .mylogin.cnf file (encrypted, not
               visible). Example : <login-path>[:<port>][:<socket>]

           o   Use a configuration file (unencrypted, not visible) Note:
               available in release-1.5.0. Example :
               <configuration-file-path>[:<section>]

           o   Specify the data on the command-line (unencrypted, visible).
               Example : <user>[:<passwd>]@<host>[:<port>][:<socket>]


       o   --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.

       o   --skip-checksum-table

           Skip the CHECKSUM TABLE step in the data consistency check. Added
           in release-1.4.3.

       o   --skip-data-check

           Skip the data consistency check.

       o   --skip-diff

           Skip the object definition difference check.

       o   --skip-object-compare

           Skip the object comparison check.

       o   --skip-row-count

           Skip the row count check.

       o   --span-key-size=<number of bytes to use for key>

           Change the size of the key used for compare table contents. A
           higher value can help to get more accurate results comparing large
           databases, but may slow the algorithm.

           Default value is 8.

       o   --ssl-ca

           The path to a file that contains a list of trusted SSL CAs.

       o   --ssl-cert

           The name of the SSL certificate file to use for establishing a
           secure connection.

       o   --ssl-cert

           The name of the SSL key file to use for establishing a secure
           connection.

       o   --ssl

           Specifies if the server connection requires use of SSL. If an
           encrypted connection cannot be established, the connection attempt
           fails. Default setting is 0 (SSL not required).

       o   --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.

       o   --version

           Display version information and exit.

       o   --use-indexes

           List the index to use. Use this option to select the index to use
           if the table has no primary key or it has more than one unique
           index without null columns. Use this option in the format:
           --use-indexes="<table1>.<indexA>[;<table2>.<indexB>;]"

       o   --width=<number>

           Change the display width of the test report. The default is 75
           characters.
       NOTES.PP The login user must have the appropriate permissions to read
       all databases and tables listed.

       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 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 compare a database with the name weird`db.name with
       other:weird`db.name, the database pair must be specified using the
       following syntax (in non-Windows):
       '`weird``db.name`:`other:weird``db.name`'.  EXAMPLES.PP Use the
       following command to compare the emp1 and emp2 databases on the local
       server, and run all tests even if earlier tests fail:

           shell> mysqldbcompare --server1=root@localhost emp1:emp2 --run-all-tests
           # server1 on localhost: ... connected.
           # Checking databases emp1 on server1 and emp2 on server2
           #
           # WARNING: Objects in server2:emp2 but not in server1:emp1:
           #   TRIGGER: trg
           # PROCEDURE: p1
           #     TABLE: t1
           #      VIEW: v1
           #
           #                                                   Defn    Row     Data
           # Type      Object Name                             Diff    Count   Check
           # ---------------------------------------------------------------------------
           # FUNCTION  f1                                      pass    -       -
           # TABLE     departments                             pass    pass    -
           #           - Compare table checksum                                FAIL
           #           - Find row differences                                  FAIL
           #
           # Data differences found among rows:
           --- emp1.departments
           +++ emp2.departments
           @@ -1,4 +1,4 @@
            *************************       1. row *************************
               dept_no: d002
           - dept_name: dunno
           + dept_name: Finance
            1 rows.
           # Rows in emp1.departments not in emp2.departments
           *************************       1. row *************************
              dept_no: d008
            dept_name: Research
           1 rows.
           # Rows in emp2.departments not in emp1.departments
           *************************       1. row *************************
              dept_no: d100
            dept_name: stupid
           1 rows.
           # TABLE     dept_manager                            pass    pass    -
           #           - Compare table checksum                                pass
           # Database consistency check failed.
           #
           # ...done

       Given: two databases with the same table layout. Data for each table
       contains:

           mysql> select * from db1.t1;
           +---+---------------+
           | a | b             |
           +---+---------------+
           | 1 | Test 789      |
           | 2 | Test 456      |
           | 3 | Test 123      |
           | 4 | New row - db1 |
           +---+---------------+
           4 rows in set (0.00 sec)
           mysql> select * from db2.t1;
           +---+---------------+
           | a | b             |
           +---+---------------+
           | 1 | Test 123      |
           | 2 | Test 456      |
           | 3 | Test 789      |
           | 5 | New row - db2 |
           +---+---------------+
           4 rows in set (0.00 sec)

       To generate the SQL statements for data transformations to make db1.t1
       the same as db2.t1, use the --changes-for=server1 option. We must also
       include the -a option to ensure that the data consistency test is run.
       The following command illustrates the options used and an excerpt from
       the results generated:

           shell> mysqldbcompare --server1=root:root@localhost \
               --server2=root:root@localhost db1:db2 --changes-for=server1 -a \/
               --difftype=sql
           [...]
           #                                                   Defn    Row     Data
           # Type      Object Name                             Diff    Count   Check
           #-------------------------------------------------------------------------
           # TABLE     t1                                      pass    pass    -
           #           - Compare table checksum                                FAIL
           #           - Find row differences                                  FAIL
           #
           # Transformation for --changes-for=server1:
           #
           # Data differences found among rows:
           UPDATE db1.t1 SET b = 'Test 123' WHERE a = '1';
           UPDATE db1.t1 SET b = 'Test 789' WHERE a = '3';
           DELETE FROM db1.t1 WHERE a = '4';
           INSERT INTO db1.t1 (a, b) VALUES('5', 'New row - db2');
           # Database consistency check failed.
           #
           # ...done

       Similarly, when the same command is run with --changes-for=server2 and
       --difftype=sql, the following report is generated:

           shell> mysqldbcompare --server1=root:root@localhost \
               --server2=root:root@localhost db1:db2 --changes-for=server2 -a \
               --difftype=sql
           [...]
           #                                                   Defn    Row     Data
           # Type      Object Name                             Diff    Count   Check
           #-------------------------------------------------------------------------
           # TABLE     t1                                      pass    pass    -
           #           - Compare table checksum                                FAIL
           #           - Find row differences                                  FAIL
           #
           # Transformation for --changes-for=server2:
           #
           # Data differences found among rows:
           UPDATE db2.t1 SET b = 'Test 789' WHERE a = '1';
           UPDATE db2.t1 SET b = 'Test 123' WHERE a = '3';
           DELETE FROM db2.t1 WHERE a = '5';
           INSERT INTO db2.t1 (a, b) VALUES('4', 'New row - db1');
           # Database consistency check failed.
           #
           # ...done

       With the --difftype=sql SQL generation option set, --show-reverse shows
       the object transformations in both directions. Here is an excerpt of
       the results:

           shell> mysqldbcompare --server1=root:root@localhost \
                     --server2=root:root@localhost db1:db2 --changes-for=server1 \
                     --show-reverse -a --difftype=sql
           [...]
           #                                                   Defn    Row     Data
           # Type      Object Name                             Diff    Count   Check
           # -------------------------------------------------------------------------
           # TABLE     t1                                      pass    pass    -
           #           - Compare table checksum                                FAIL
           #           - Find row differences                                  FAIL
           #
           # Transformation for --changes-for=server1:
           #
           # Data differences found among rows:
           UPDATE db1.t1 SET b = 'Test 123' WHERE a = '1';
           UPDATE db1.t1 SET b = 'Test 789' WHERE a = '3';
           DELETE FROM db1.t1 WHERE a = '4';
           INSERT INTO db1.t1 (a, b) VALUES('5', 'New row - db2');
           #
           # Transformation for reverse changes (--changes-for=server2):
           #
           # # Data differences found among rows:
           # UPDATE db2.t1 SET b = 'Test 789' WHERE a = '1';
           # UPDATE db2.t1 SET b = 'Test 123' WHERE a = '3';
           # DELETE FROM db2.t1 WHERE a = '5';
           # INSERT INTO db2.t1 (a, b) VALUES('4', 'New row - db1');
           # Database consistency check failed.
           #
           # ...done

       PERMISSIONS REQUIRED.PP The user must have the SELECT, CREATE TEMPORARY
       TABLES and INSERT privileges for the databases being compared on both
       connections. The user must also have SELECT privilege on the mysql
       database. If the binary log is enabled and the --disable-binary-logging
       option is used, the user must also have the SUPER privilege.

COPYRIGHT
       Copyright (C) 2006, 2015, Oracle and/or its affiliates. All rights
       reserved.

       This documentation is free software; you can redistribute it and/or
       modify it only under the terms of the GNU General Public License as
       published by the Free Software Foundation; version 2 of the License.

       This documentation is distributed in the hope that it will be useful,
       but WITHOUT ANY WARRANTY; without even the implied warranty of
       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
       General Public License for more details.

       You should have received a copy of the GNU General Public License along
       with the program; if not, write to the Free Software Foundation, Inc.,
       51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or see
       http://www.gnu.org/licenses/.


SEE ALSO
       For more information, please refer to the MySQL Utilities and Fabric
       documentation, which is available online at
       http://dev.mysql.com/doc/index-utils-fabric.html

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



MySQL 1.5.6                       09/15/2015                 MYSQLDBCOMPARE(1)
