Implement SQL99 OVERLAY(). Allows substitution of a substring in a string.

Implement SQL99 SIMILAR TO as a synonym for our existing operator "~".
Implement SQL99 regular expression SUBSTRING(string FROM pat FOR escape).
 Extend the definition to make the FOR clause optional.
 Define textregexsubstr() to actually implement this feature.
Update the regression test to include these new string features.
 All tests pass.
Rename the regular expression support routines from "pg95_xxx" to "pg_xxx".
Define CREATE CHARACTER SET in the parser per SQL99. No implementation yet.

doc/src/sgml/advanced.sgml

@@ -1,5 +1,5 @@
 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/advanced.sgml,v 1.27 2002/02/12 22:25:15 momjian Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/advanced.sgml,v 1.28 2002/06/11 15:32:32 thomas Exp $
 -->
 
  <chapter id="tutorial-advanced">
@@ -114,7 +114,6 @@ CREATE TABLE weather (
 	prcp      real,
 	date      date
 );
-
     </programlisting>
 
     Now try inserting an invalid record:
@@ -126,7 +125,6 @@ INSERT INTO weather VALUES ('Berkeley', 45, 53, 0.0, '1994-11-28');
     <screen>
 ERROR:  &lt;unnamed&gt; referential integrity violation - key referenced from weather not found in cities
     </screen>
-
    </para>
 
    <para>
@@ -162,6 +160,7 @@ ERROR:  &lt;unnamed&gt; referential integrity violation - key referenced from we
     Suppose that we want to record a payment of $100.00 from Alice's account
     to Bob's account.  Simplifying outrageously, the SQL commands for this
     might look like
+
     <programlisting>
 UPDATE accounts SET balance = balance - 100.00
     WHERE name = 'Alice';
@@ -172,6 +171,9 @@ UPDATE accounts SET balance = balance + 100.00
 UPDATE branches SET balance = balance + 100.00
     WHERE name = (SELECT branch_name FROM accounts WHERE name = 'Bob');
     </programlisting>
+   </para>
+
+   <para>
     The details of these commands are not important here; the important
     point is that there are several separate updates involved to accomplish
     this rather simple operation.  Our bank's officers will want to be
@@ -219,6 +221,7 @@ UPDATE branches SET balance = balance + 100.00
     the SQL commands of the transaction with
     <command>BEGIN</> and <command>COMMIT</> commands.  So our banking
     transaction would actually look like
+
     <programlisting>
 BEGIN;
 UPDATE accounts SET balance = balance - 100.00
@@ -226,6 +229,9 @@ UPDATE accounts SET balance = balance - 100.00
 -- etc etc
 COMMIT;
     </programlisting>
+   </para>
+
+   <para>
     If, partway through the transaction, we decide we don't want to
     commit (perhaps we just noticed that Alice's balance went negative),
     we can issue the command <command>ROLLBACK</> instead of
@@ -310,7 +316,9 @@ CREATE TABLE capitals (
   state      char(2)
 ) INHERITS (cities);
     </programlisting>
+   </para>
 
+   <para>
     In this case, a row of <classname>capitals</classname>
     <firstterm>inherits</firstterm> all columns (<structfield>name</>,
     <structfield>population</>, and <structfield>altitude</>) from its
@@ -397,7 +405,6 @@ SELECT name, altitude
     site</ulink> for links to more resources.
    </para>
   </sect1>
-
  </chapter>
 
 <!-- Keep this comment at the end of the file

doc/src/sgml/datatype.sgml

@@ -1,5 +1,5 @@
 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.92 2002/05/03 04:11:07 tgl Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.93 2002/06/11 15:32:32 thomas Exp $
 -->
 
  <chapter id="datatype">
@@ -2637,7 +2637,8 @@ SELECT * FROM test1 WHERE a;
      The <type>inet</type> type holds an IP host address, and
      optionally the identity of the subnet it is in, all in one field.
      The subnet identity is represented by the number of bits in the
-     network part of the address (the <quote>netmask</quote>).  If the netmask is 32,
+     network part of the address (the <quote>netmask</quote>).  If the
+     netmask is 32, 
      then the value does not indicate a subnet, only a single host.
      Note that if you want to accept networks only, you should use the
      <type>cidr</type> type rather than <type>inet</type>.

doc/src/sgml/release.sgml

@@ -1,5 +1,5 @@
 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/release.sgml,v 1.138 2002/05/22 17:20:58 petere Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/release.sgml,v 1.139 2002/06/11 15:32:33 thomas Exp $
 -->
 
 <appendix id="release">
@@ -44,6 +44,9 @@ Access privileges on procedural languages
 CREATE DATABASE has OWNER option so superuser can create DB for someone else
 Kerberos 5 support now works with Heimdal
 Database and user-specific session defaults for run-time configuration variables (ALTER DATABASE ... SET and ALTER USER ... SET)
+String function OVERLAY() implemented per SQL99
+Regular expression operator SIMILAR TO implemented per SQL99
+Regular expression function SUBSTRING() implemented per SQL99
 ]]></literallayout>
 
  </sect1>