Provided by: postfix_3.10.2-1ubuntu1_amd64 bug

NAME

       mysql_table - Postfix MySQL client configuration

SYNOPSIS

       postmap -q "string" mysql:/etc/postfix/filename

       postmap -q - mysql:/etc/postfix/filename <inputfile

DESCRIPTION

       The  Postfix  mail  system  uses  optional tables for address rewriting or mail routing. These tables are
       usually in dbm or db format.

       Alternatively, lookup tables can be specified as MySQL databases.  In order to use MySQL lookups,  define
       a MySQL source as a lookup table in main.cf, for example:
           alias_maps = mysql:/etc/postfix/mysql-aliases.cf

       The  file  /etc/postfix/mysql-aliases.cf has the same format as the Postfix main.cf file, and can specify
       the parameters described below.

LIST MEMBERSHIP

       When using SQL to store lists such as $mynetworks, $mydestination, $relay_domains, $local_recipient_maps,
       etc., it is important to understand that the table must store each list member as  a  separate  key.  The
       table   lookup  verifies  the  *existence*  of  the  key.  See  "Postfix  lists  versus  tables"  in  the
       DATABASE_README document for a discussion.

       Do NOT create tables that return the full list of domains in $mydestination or $relay_domains etc., or IP
       addresses in $mynetworks.

       DO create tables with each matching item as a key and with an arbitrary value. With SQL databases  it  is
       not uncommon to return the key itself or a constant value.

MYSQL PARAMETERS

       hosts  The  hosts  that  Postfix  will  try  to connect to and query from.  Specify unix: for UNIX domain
              sockets, inet: for TCP connections (default).  Examples:
                  hosts = inet:host1.some.domain inet:host2.some.domain:port
                  hosts = host1.some.domain host2.some.domain:port
                  hosts = unix:/file/name

              The hosts are tried in random order, with all connections over UNIX  domain  sockets  being  tried
              before  those  over  TCP.   The  connections are automatically closed after being idle for about 1
              minute, and are re-opened as necessary. Postfix versions 2.0 and earlier do not randomize the host
              order.

              NOTE: if you specify localhost as a hostname (even if  you  prefix  it  with  inet:),  MySQL  will
              connect  to  the  default  UNIX domain socket.  In order to instruct MySQL to connect to localhost
              over TCP you have to specify
                  hosts = 127.0.0.1

              NOTE: if the hosts setting specifies one server, this client assumes that the  target  is  a  load
              balancer  and  will  reconnect immediately after a single failure, instead of failing all requests
              temporarily. With older versions of this client, specify the same server twice.

       user

       password
              The user name and password to log into the mysql server.  Example:
                  user = someone
                  password = some_password

       dbname The database name on the servers. Example:
                  dbname = customer_database

       charset (default: utf8mb4)
              The default MySQL client character set; this also implies the collation order.

              This parameter is available with Postfix 3.9  and  later.   With  earlier  Postfix  versions,  the
              default was chosen by the MySQL implementation (utf8mb4 as of MySQL 8.0, latin1 historically).

       idle_interval (default: 60)
              The number of seconds after which an idle database connection will be closed.

              This feature is available in Postfix 3.9 and later.

       retry_interval (default: 60)
              The number of seconds that a database connection will be skipped after an error.

              NOTE:  if  the  hosts  setting specifies one server, this client assumes that the target is a load
              balancer and will reconnect immediately after a single failure, instead of  failing  all  requests
              temporarily. With older versions of this client, specify the same server twice.

              This feature is available in Postfix 3.9 and later.

       query  The  SQL  query  template  used  to  search the database, where %s is a substitute for the address
              Postfix is trying to resolve, e.g.
                  query = SELECT replacement FROM aliases WHERE mailbox = '%s'

              By default, every query must return a result set (instead of storing its results in a table); with
              "require_result_set = no" (Postfix 3.2 and later), the absence of a result set is treated as  "not
              found".

              This parameter supports the following '%' expansions:

              %%     This is replaced by a literal '%' character.

              %s     This  is  replaced  by  the input key.  SQL quoting is used to make sure that the input key
                     does not add unexpected metacharacters.

              %u     When the input key is an address of the form user@domain, %u is replaced by the SQL  quoted
                     local  part of the address.  Otherwise, %u is replaced by the entire search string.  If the
                     localpart is empty, the query is suppressed and returns no results.

              %d     When the input key is an address of the form user@domain, %d is replaced by the SQL  quoted
                     domain part of the address.  Otherwise, the query is suppressed and returns no results.

              %[SUD] The  upper-case  equivalents  of  the  above  expansions  behave  in  the  query  parameter
                     identically to their lower-case  counter-parts.   With  the  result_format  parameter  (see
                     below), they expand the input key rather than the result value.

              %[1-9] The patterns %1, %2, ... %9 are replaced by the corresponding most significant component of
                     the  input  key's  domain. If the input key is user@mail.example.com, then %1 is com, %2 is
                     example and %3 is mail. If the input key is unqualified or  does  not  have  enough  domain
                     components  to  satisfy  all the specified patterns, the query is suppressed and returns no
                     results.

              The domain parameter described below limits the input keys to addresses in matching domains.  When
              the  domain  parameter  is  non-empty,  SQL  queries  for  unqualified  addresses  or addresses in
              non-matching domains are suppressed and return no results.

              This parameter is available with Postfix 2.2. In prior releases the SQL query was built  from  the
              separate  parameters: select_field, table, where_field and additional_conditions. The mapping from
              the old parameters to the equivalent query is:

                  SELECT [select_field]
                  FROM [table]
                  WHERE [where_field] = '%s'
                        [additional_conditions]

              The '%s' in the WHERE clause expands to the escaped search string.  With Postfix 2.2 these  legacy
              parameters are used if the query parameter is not specified.

              NOTE: DO NOT put quotes around the query parameter.

       result_format (default: %s)
              Format  template  applied  to result attributes. Most commonly used to append (or prepend) text to
              the result. This parameter supports the following '%' expansions:

              %%     This is replaced by a literal '%' character.

              %s     This is replaced by the value of the result attribute. When result is empty it is skipped.

              %u     When the result attribute value is an address of the form user@domain, %u  is  replaced  by
                     the local part of the address. When the result has an empty localpart it is skipped.

              %d     When  a result attribute value is an address of the form user@domain, %d is replaced by the
                     domain part of the attribute value. When the result is unqualified it is skipped.

              %[SUD1-9]
                     The upper-case and decimal digit expansions interpolate the parts of the input  key  rather
                     than  the  result.  Their  behavior  is identical to that described with query, and in fact
                     because the input key is known in advance, queries whose  key  does  not  contain  all  the
                     information specified in the result template are suppressed and return no results.

              For example, using "result_format = smtp:[%s]" allows one to use a mailHost attribute as the basis
              of  a  transport(5)  table.  After applying the result format, multiple values are concatenated as
              comma separated strings. The expansion_limit and parameter explained below allows one to  restrict
              the  number  of values in the result, which is especially useful for maps that must return at most
              one value.

              The default value %s specifies that each result value should be used as is.

              This parameter is available with Postfix 2.2 and later.

              NOTE: DO NOT put quotes around the result format!

       domain (default: no domain list)
              This is a list of domain names, paths to files, or "type:table" databases.  When  specified,  only
              fully  qualified  search  keys with a *non-empty* localpart and a matching domain are eligible for
              lookup: 'user' lookups, bare domain lookups and "@domain" lookups  are  not  performed.  This  can
              significantly reduce the query load on the MySQL server.
                  domain = postfix.org, hash:/etc/postfix/searchdomains

              It is best not to use SQL to store the domains eligible for SQL lookups.

              This parameter is available with Postfix 2.2 and later.

              NOTE:  DO  NOT  define  this  parameter  for  local(8)  aliases, because the input keys are always
              unqualified.

       expansion_limit (default: 0)
              A limit on the total number of result elements returned (as a comma separated list)  by  a  lookup
              against the map.  A setting of zero disables the limit. Lookups fail with a temporary error if the
              limit is exceeded.  Setting the limit to 1 ensures that lookups do not return multiple values.

       option_file
              Read  options  from the given file instead of the default my.cnf location. This reads options from
              the [client] option group, optionally followed by options from the group given with option_group.

              This parameter is available with Postfix 2.11 and later.

       option_group (default: Postfix >=3.2: client, <= 3.1: empty)
              Read options from the given group of the mysql  options  file,  after  reading  options  from  the
              [client] group.

              Postfix  3.2  and later read [client] option group settings by default. To disable this specify no
              option_file and specify "option_group =" (i.e. an empty value).

              Postfix 3.1 and earlier don't read [client] option group settings unless a  non-empty  option_file
              or  option_group  value  are  specified.  To  enable  this,  specify, for example, "option_group =
              client".

              This parameter is available with Postfix 2.11 and later.

       require_result_set (default: yes)
              If "yes", require that every query returns a result set.  If "no", treat the absence of  a  result
              set as "not found".

              This parameter is available with Postfix 3.2 and later.

TLS-RELATED SETTINGS

       See  https://dev.mysql.com/doc/c-api/en/mysql-options.html  or  https://mariadb.com/kb/en/mysql_optionsv/
       for details of the underlying MYSQL_OPT_SSL_* features.

       tls_cert_file
              File containing client's X509 certificate.

              This parameter is available with Postfix 2.11 and later.

       tls_key_file
              File containing the private key corresponding to tls_cert_file.

              This parameter is available with Postfix 2.11 and later.

       tls_CAfile
              File containing X509 certificates for  all  of  the  Certification  Authorities  the  client  will
              recognize.  Takes precedence over tls_CApath.

              This parameter is available with Postfix 2.11 and later.

       tls_CApath
              Directory containing X509 Certification Authority certificates in separate individual files.

              This parameter is available with Postfix 2.11 and later.

       tls_ciphers
              The list of permissible ciphers for SSL encryption.

              This parameter is available with Postfix 2.11 and later.

       tls_verify_cert (default: no)
              Verify that the server's name matches the common name in the certificate.

              This parameter is available with Postfix 2.11 and later.

USING MYSQL STORED PROCEDURES

       Postfix  3.2  and  later  support  calling  a stored procedure instead of using a SELECT statement in the
       query, e.g.

           query = CALL lookup('%s')

       The previously described '%' expansions can be used in the parameter(s) to the stored procedure.

       By default, every stored procedure call must return a result set, i.e. every code  path  must  execute  a
       SELECT  statement  that  returns  a  result  set  (instead  of  storing  its  results  in  a table). With
       "require_result_set = no", the absence of a result set is treated as "not found".

       A stored procedure must not return multiple result sets.  That is,  there  must  be  no  code  path  that
       executes multiple SELECT statements that return a result (instead of storing their results in a table).

       The following is an example of a stored procedure returning a single result set:

       CREATE [DEFINER=`user`@`host`] PROCEDURE
       `lookup`(IN `param` VARCHAR(255))
           READS SQL DATA
           SQL SECURITY INVOKER
           BEGIN
               select goto from alias where address=param;
           END

OBSOLETE MAIN.CF PARAMETERS

       For  compatibility with other Postfix lookup tables, MySQL parameters can also be defined in main.cf.  In
       order to do that, specify as MySQL source a name that doesn't begin with a slash or  a  dot.   The  MySQL
       parameters  will then be accessible as the name you've given the source in its definition, an underscore,
       and the name of the parameter.  For example, if the map is specified as "mysql:mysqlname", the  parameter
       "hosts" would be defined in main.cf as "mysqlname_hosts".

       Note:  with  this  form,  the  passwords  for the MySQL sources are written in main.cf, which is normally
       world-readable.  Support for this form will be removed in a future Postfix version.

OBSOLETE QUERY INTERFACE

       This section describes an interface that is deprecated as of Postfix 2.2. It  is  replaced  by  the  more
       general  query  interface  described  above.  If  the  query  parameter is defined, the legacy parameters
       described here ignored.  Please migrate to the new interface as the legacy interface may be removed in  a
       future release.

       The following parameters can be used to fill in a SELECT template statement of the form:

           SELECT [select_field]
           FROM [table]
           WHERE [where_field] = '%s'
                 [additional_conditions]

       The  specifier  %s  is  replaced  by the search string, and is escaped so if it contains single quotes or
       other odd characters, it will not cause a parse error, or worse, a security problem.

       select_field
              The SQL "select" parameter. Example:
                  select_field = forw_addr

       table  The SQL "select .. from" table name. Example:
                  table = mxaliases

       where_field
              The SQL "select .. where" parameter. Example:
                  where_field = alias

       additional_conditions
              Additional conditions to the SQL query. Example:
                  additional_conditions = AND status = 'paid'

SEE ALSO

       postmap(1), Postfix lookup table maintenance
       postconf(5), configuration parameters
       ldap_table(5), LDAP lookup tables
       pgsql_table(5), PostgreSQL lookup tables
       sqlite_table(5), SQLite lookup tables

README FILES

       Use "postconf readme_directory" or "postconf html_directory" to locate this information.
       DATABASE_README, Postfix lookup table overview
       MYSQL_README, Postfix MYSQL client guide

LICENSE

       The Secure Mailer license must be distributed with this software.

HISTORY

       MySQL support was introduced with Postfix version 1.0.

AUTHOR(S)

       Original implementation by:
       Scott Cotton, Joshua Marcus
       IC Group, Inc.

       Further enhancements by:
       Liviu Daia
       Institute of Mathematics of the Romanian Academy
       P.O. BOX 1-764
       RO-014700 Bucharest, ROMANIA

       Stored-procedure support by John Fawcett.

       Wietse Venema
       Google, Inc.
       111 8th Avenue
       New York, NY 10011, USA

                                                                                                  MYSQL_TABLE(5)