    MYSQL_TABLE(5)                                                  MYSQL_TABLE(5)

    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/mysql-aliases.cf

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

    BACKWARDS COMPATIBILITY
           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 def-
           inition, an underscore, and the  name  of  the  parameter.
           For example, if the map is specified as "mysql:mysqlname",
           the parameter "hosts" below 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.

           Postfix 2.2 has enhanced query interfaces  for  MySQL  and
           PostgreSQL;  these  include  features previously available
           only in the Postfix LDAP client. In the new interface  the
           SQL  query  is  specified  via  a  single  query parameter
           (described in more detail  below).   When  the  new  query
           parameter  is not specified in the map definition, Postfix
           reverts to the old interface,  with  the  SQL  query  con-
           structed  from  the  select_field,  table, where_field and
           additional_conditions parameters.  The old interface  will
           be  gradually  phased out. To migrate to the new interface
           set:

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

           Insert the value, not the name, of each legacy  parameter.
           Note  that the additional_conditions parameter is optional
           and if not empty, will always start with AND.

    LIST MEMBERSHIP
           When using SQL to store lists such as $mynetworks, $mydes-
           tination,  $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).  Example:
                      hosts = host1.some.domain host2.some.domain
                      hosts = unix:/file/name

                  The hosts are tried in random order, with all  con-
                  nections  over  UNIX  domain  sockets  being  tried
                  before those over TCP.  The connections  are  auto-
                  matically  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

           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

           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'

                  This  parameter  supports  the following '%' expan-
                  sions:

                  %%     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.   Other-
                         wise,  %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.   Other-
                         wise, 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 speci-
                         fied 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 parame-
                  ter explained below allows one to restrict the num-
                  ber  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
                  dictionaries. 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 eli-
                  gible 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 unquali-
                  fied.

           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.

    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  inter-
           face 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 char-
           acters, it will not cause a parse error, or worse, a secu-
           rity 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

    README FILES
           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

                                                                    MYSQL_TABLE(5)