.\"	$NetBSD: mysql_table.5,v 1.2.14.1 2023/12/25 12:54:40 martin Exp $
.\"
.TH MYSQL_TABLE 5 
.ad
.fi
.SH NAME
mysql_table
\-
Postfix MySQL client configuration
.SH "SYNOPSIS"
.na
.nf
\fBpostmap \-q "\fIstring\fB" mysql:/etc/postfix/\fIfilename\fR

\fBpostmap \-q \- mysql:/etc/postfix/\fIfilename\fB <\fIinputfile\fR
.SH DESCRIPTION
.ad
.fi
The Postfix mail system uses optional tables for address
rewriting or mail routing. These tables are usually in
\fBdbm\fR or \fBdb\fR 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:
.nf
    alias_maps = mysql:/etc/postfix/mysql\-aliases.cf
.fi

The file /etc/postfix/mysql\-aliases.cf has the same format as
the Postfix main.cf file, and can specify the parameters
described below.
.SH "LIST MEMBERSHIP"
.na
.nf
.ad
.fi
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.
.SH "MYSQL PARAMETERS"
.na
.nf
.ad
.fi
.IP "\fBhosts\fR"
The hosts that Postfix will try to connect to and query from.
Specify \fIunix:\fR for UNIX domain sockets, \fIinet:\fR for TCP
connections (default).  Examples:
.nf
    hosts = inet:host1.some.domain inet:host2.some.domain:port
    hosts = host1.some.domain host2.some.domain:port
    hosts = unix:/file/name
.fi

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 \fIinet:\fR), MySQL will connect to the default
UNIX domain socket.  In order to instruct MySQL to connect to
localhost over TCP you have to specify
.nf
    hosts = 127.0.0.1
.fi
.IP "\fBuser\fR"
.IP "\fBpassword\fR"
The user name and password to log into the mysql server.
Example:
.nf
    user = someone
    password = some_password
.fi
.IP "\fBdbname\fR"
The database name on the servers. Example:
.nf
    dbname = customer_database
.fi
.IP "\fBquery\fR"
The SQL query template used to search the database, where \fB%s\fR
is a substitute for the address Postfix is trying to resolve,
e.g.
.nf
    query = SELECT replacement FROM aliases WHERE mailbox = '%s'
.fi

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

This parameter supports the following '%' expansions:
.RS
.IP "\fB%%\fR"
This is replaced by a literal '%' character.
.IP "\fB%s\fR"
This is replaced by the input key.
SQL quoting is used to make sure that the input key does not
add unexpected metacharacters.
.IP "\fB%u\fR"
When the input key is an address of the form user@domain, \fB%u\fR
is replaced by the SQL quoted local part of the address.
Otherwise, \fB%u\fR is replaced by the entire search string.
If the localpart is empty, the query is suppressed and returns
no results.
.IP "\fB%d\fR"
When the input key is an address of the form user@domain, \fB%d\fR
is replaced by the SQL quoted domain part of the address.
Otherwise, the query is suppressed and returns no results.
.IP "\fB%[SUD]\fR"
The upper\-case equivalents of the above expansions behave in the
\fBquery\fR parameter identically to their lower\-case counter\-parts.
With the \fBresult_format\fR parameter (see below), they expand the
input key rather than the result value.
.IP "\fB%[1\-9]\fR"
The patterns %1, %2, ... %9 are replaced by the corresponding
most significant component of the input key's domain. If the
input key is \fIuser@mail.example.com\fR, then %1 is \fBcom\fR,
%2 is \fBexample\fR and %3 is \fBmail\fR. 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.
.RE
.IP
The \fBdomain\fR parameter described below limits the input
keys to addresses in matching domains. When the \fBdomain\fR
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:
\fBselect_field\fR, \fBtable\fR, \fBwhere_field\fR and
\fBadditional_conditions\fR. The mapping from the old parameters
to the equivalent query is:

.nf
    SELECT [\fBselect_field\fR]
    FROM [\fBtable\fR]
    WHERE [\fBwhere_field\fR] = '%s'
          [\fBadditional_conditions\fR]
.fi

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

NOTE: DO NOT put quotes around the query parameter.
.IP "\fBresult_format (default: \fB%s\fR)\fR"
Format template applied to result attributes. Most commonly used
to append (or prepend) text to the result. This parameter supports
the following '%' expansions:
.RS
.IP "\fB%%\fR"
This is replaced by a literal '%' character.
.IP "\fB%s\fR"
This is replaced by the value of the result attribute. When
result is empty it is skipped.
.IP "\fB%u\fR
When the result attribute value is an address of the form
user@domain, \fB%u\fR is replaced by the local part of the
address. When the result has an empty localpart it is skipped.
.IP "\fB%d\fR"
When a result attribute value is an address of the form
user@domain, \fB%d\fR is replaced by the domain part of
the attribute value. When the result is unqualified it
is skipped.
.IP "\fB%[SUD1\-9]\fR"
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 \fBquery\fR,
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.
.RE
.IP
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 \fB%s\fR 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!
.IP "\fBdomain (default: no domain list)\fR"
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.
.nf
    domain = postfix.org, hash:/etc/postfix/searchdomains
.fi

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.
.IP "\fBexpansion_limit (default: 0)\fR"
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.
.IP "\fBoption_file\fR"
Read options from the given file instead of the default my.cnf
location. This reads options from the \fB[client]\fR option
group, optionally followed by options from the group given
with \fBoption_group\fR.
.sp
This parameter is available with Postfix 2.11 and later.
.IP "\fBoption_group (default: Postfix >=3.2: client, <= 3.1: empty)\fR"
Read options from the given group of the mysql options file,
after reading options from the \fB[client]\fR group.
.sp
Postfix 3.2 and later read \fB[client]\fR option group
settings by default. To disable this specify no \fBoption_file\fR
and specify "\fBoption_group =\fR" (i.e. an empty value).
.sp
Postfix 3.1 and earlier don't read \fB[client]\fR option
group settings unless a non\-empty \fBoption_file\fR or
\fBoption_group\fR value are specified. To enable this,
specify, for example, "\fBoption_group = client\fR".
.sp
This parameter is available with Postfix 2.11 and later.
.IP "\fBrequire_result_set (default: yes)\fR"
If "\fByes\fR", require that every query returns a result
set.  If "\fBno\fR", treat the absence of a result set as
"not found".
.sp
This parameter is available with Postfix 3.2 and later.
.IP "\fBtls_cert_file\fR"
File containing client's X509 certificate.
.sp
This parameter is available with Postfix 2.11 and later.
.IP "\fBtls_key_file\fR"
File containing the private key corresponding to \fBtls_cert_file\fR.
.sp
This parameter is available with Postfix 2.11 and later.
.IP "\fBtls_CAfile\fR"
File containing certificates for all of the X509 Certification
Authorities the client will recognize.  Takes precedence over
\fBtls_CApath\fR.
.sp
This parameter is available with Postfix 2.11 and later.
.IP "\fBtls_CApath\fR"
Directory containing X509 Certification Authority certificates
in separate individual files.
.sp
This parameter is available with Postfix 2.11 and later.
.IP "\fBtls_ciphers\fR"
The list of permissible ciphers for SSL encryption.
.sp
This parameter is available with Postfix 2.11 and later.
.IP "\fBtls_verify_cert (default: no)\fR"
Verify that the server's name matches the common name in the
certificate.
.sp
This parameter is available with Postfix 2.11 and later.
.SH "USING MYSQL STORED PROCEDURES"
.na
.nf
.ad
.fi
Postfix 3.2 and later support calling a stored procedure
instead of using a SELECT statement in the query, e.g.

.nf
    \fBquery\fR = CALL lookup('%s')
.fi

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 "\fBrequire_result_set = no\fR", 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:

.nf
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
.fi
.SH "OBSOLETE MAIN.CF PARAMETERS"
.na
.nf
.ad
.fi
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:\fImysqlname\fR", the parameter "hosts"
would be defined in main.cf as "\fImysqlname\fR_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.
.SH "OBSOLETE QUERY INTERFACE"
.na
.nf
.ad
.fi
This section describes an interface that is deprecated as
of Postfix 2.2. It is replaced by the more general \fBquery\fR
interface described above. If the \fBquery\fR 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:

.nf
    SELECT [\fBselect_field\fR]
    FROM [\fBtable\fR]
    WHERE [\fBwhere_field\fR] = '%s'
          [\fBadditional_conditions\fR]
.fi

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.
.IP "\fBselect_field\fR"
The SQL "select" parameter. Example:
.nf
    \fBselect_field\fR = forw_addr
.fi
.IP "\fBtable\fR"
The SQL "select .. from" table name. Example:
.nf
    \fBtable\fR = mxaliases
.fi
.IP "\fBwhere_field\fR
The SQL "select .. where" parameter. Example:
.nf
    \fBwhere_field\fR = alias
.fi
.IP "\fBadditional_conditions\fR
Additional conditions to the SQL query. Example:
.nf
    \fBadditional_conditions\fR = AND status = 'paid'
.fi
.SH "SEE ALSO"
.na
.nf
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
.SH "README FILES"
.na
.nf
.ad
.fi
Use "\fBpostconf readme_directory\fR" or
"\fBpostconf html_directory\fR" to locate this information.
.na
.nf
DATABASE_README, Postfix lookup table overview
MYSQL_README, Postfix MYSQL client guide
.SH "LICENSE"
.na
.nf
.ad
.fi
The Secure Mailer license must be distributed with this software.
.SH HISTORY
.ad
.fi
MySQL support was introduced with Postfix version 1.0.
.SH "AUTHOR(S)"
.na
.nf
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