diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index 98b69380b6..ad5e9b95b4 100644
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -892,8 +892,8 @@ postgresql://%2Fvar%2Flib%2Fpostgresql/dbname
<title>Specifying Multiple Hosts</title>
<para>
- It is possible to specify multiple hosts to connect to, so that they are
- tried in the given order. In the Keyword/Value format, the <literal>host</>,
+ It is possible to specify multiple hosts to connect to, so that they are
+ tried in the given order. In the Keyword/Value format, the <literal>host</>,
<literal>hostaddr</>, and <literal>port</> options accept a comma-separated
list of values. The same number of elements must be given in each option, such
that e.g. the first <literal>hostaddr</> corresponds to the first host name,
@@ -903,24 +903,24 @@ postgresql://%2Fvar%2Flib%2Fpostgresql/dbname
</para>
<para>
- In the connection URI format, you can list multiple <literal>host:port</> pairs
+ In the connection URI format, you can list multiple <literal>host:port</> pairs
separated by commas, in the <literal>host</> component of the URI. In either
format, a single hostname can also translate to multiple network addresses. A
common example of this is a host that has both an IPv4 and an IPv6 address.
</para>
<para>
- When multiple hosts are specified, or when a single hostname is
- translated to multiple addresses, all the hosts and addresses will be
- tried in order, until one succeeds. If none of the hosts can be reached,
- the connection fails. If a connection is established successfully, but
+ When multiple hosts are specified, or when a single hostname is
+ translated to multiple addresses, all the hosts and addresses will be
+ tried in order, until one succeeds. If none of the hosts can be reached,
+ the connection fails. If a connection is established successfully, but
authentication fails, the remaining hosts in the list are not tried.
</para>
<para>
- If a password file is used, you can have different passwords for
- different hosts. All the other connection options are the same for every
- host, it is not possible to e.g. specify a different username for
+ If a password file is used, you can have different passwords for
+ different hosts. All the other connection options are the same for every
+ host, it is not possible to e.g. specify a different username for
different hosts.
</para>
</sect3>
@@ -1844,17 +1844,36 @@ int PQprotocolVersion(const PGconn *conn);
<listitem>
<para>
- Returns an integer representing the backend version.
+ Returns an integer representing the server version.
<synopsis>
int PQserverVersion(const PGconn *conn);
</synopsis>
- Applications might use this function to determine the version of the database
- server they are connected to. The number is formed by converting
- the major, minor, and revision numbers into two-decimal-digit
- numbers and appending them together. For example, version 8.1.5
- will be returned as 80105, and version 8.2 will be returned as
- 80200 (leading zeroes are not shown). Zero is returned if the
- connection is bad.
+ </para>
+
+ <para>
+ Applications might use this function to determine the version of the
+ database server they are connected to. The result is formed by
+ multiplying the server's major version number by 10000 and adding
+ the minor version number. For example, version 10.1 will be
+ returned as 100001, and version 11.0 will be returned as 110000.
+ Zero is returned if the connection is bad.
+ </para>
+
+ <para>
+ Prior to major version 10, <productname>PostgreSQL</> used
+ three-part version numbers in which the first two parts together
+ represented the major version. For those
+ versions, <function>PQserverVersion</> uses two digits for each
+ part; for example version 9.1.5 will be returned as 90105, and
+ version 9.2.0 will be returned as 90200.
+ </para>
+
+ <para>
+ Therefore, for purposes of determining feature compatibility,
+ applications should divide the result of <function>PQserverVersion</>
+ by 100 not 10000 to determine a logical major version number.
+ In all release series, only the last two digits differ between
+ minor releases (bug-fix releases).
</para>
</listitem>
</varlistentry>
@@ -6224,26 +6243,42 @@ int PQlibVersion(void);
<para>
The result of this function can be used to determine, at
- run time, if specific functionality is available in the currently
+ run time, whether specific functionality is available in the currently
loaded version of libpq. The function can be used, for example,
- to determine which connection options are available for
- <function>PQconnectdb</> or if the <literal>hex</> <type>bytea</>
- output added in PostgreSQL 9.0 is supported.
+ to determine which connection options are available in
+ <function>PQconnectdb</>.
</para>
<para>
- The number is formed by converting the major, minor, and revision
- numbers into two-decimal-digit numbers and appending them together.
- For example, version 9.1 will be returned as 90100, and version
- 9.1.2 will be returned as 90102 (leading zeroes are not shown).
+ The result is formed by multiplying the library's major version
+ number by 10000 and adding the minor version number. For example,
+ version 10.1 will be returned as 100001, and version 11.0 will be
+ returned as 110000.
+ </para>
+
+ <para>
+ Prior to major version 10, <productname>PostgreSQL</> used
+ three-part version numbers in which the first two parts together
+ represented the major version. For those
+ versions, <function>PQlibVersion</> uses two digits for each
+ part; for example version 9.1.5 will be returned as 90105, and
+ version 9.2.0 will be returned as 90200.
+ </para>
+
+ <para>
+ Therefore, for purposes of determining feature compatibility,
+ applications should divide the result of <function>PQlibVersion</>
+ by 100 not 10000 to determine a logical major version number.
+ In all release series, only the last two digits differ between
+ minor releases (bug-fix releases).
</para>
<note>
<para>
This function appeared in <productname>PostgreSQL</> version 9.1, so
it cannot be used to detect required functionality in earlier
- versions, since linking to it will create a link dependency
- on version 9.1.
+ versions, since calling it will create a link dependency
+ on version 9.1 or later.
</para>
</note>
</listitem>