From 32ba4920455f2bfa092a034bcf6268bce35a03e3 Mon Sep 17 00:00:00 2001
From: Dilip Kumar <dilipkumar@localhost.localdomain>
Date: Fri, 11 Mar 2022 11:48:55 +0530
Subject: [PATCH v15 6/6] Support create database strategy in createdb tool

---
 doc/src/sgml/ref/createdb.sgml    | 16 ++++++++++++++++
 src/bin/scripts/createdb.c        | 10 +++++++++-
 src/bin/scripts/t/020_createdb.pl | 20 ++++++++++++++++++++
 3 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/ref/createdb.sgml b/doc/src/sgml/ref/createdb.sgml
index 8647345..2a7beca 100644
--- a/doc/src/sgml/ref/createdb.sgml
+++ b/doc/src/sgml/ref/createdb.sgml
@@ -159,6 +159,22 @@ PostgreSQL documentation
      </varlistentry>
 
      <varlistentry>
+      <term><option>-S <replaceable class="parameter">template</replaceable></option></term>
+      <term><option>--strategy=<replaceable class="parameter">strategy</replaceable></option></term>
+      <listitem>
+       <para>
+        Specifies the database creation strategy.  Currently, we have two
+        strategies the <literal>WAL_LOG</literal> and the <literal>FILE_COPY
+        </literal>.  If <literal>WAL_LOG</literal> strategy is used then the
+        database will be copied block by block and it will also WAL log each
+        copied block.  Otherwise, if <literal>FILE_COPY</literal> strategy is
+        used then it will do the file system level copy so individual the block
+        is not WAL logged.  The default strategy is <literal>WAL_LOG</literal>.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
       <term><option>-T <replaceable class="parameter">template</replaceable></option></term>
       <term><option>--template=<replaceable class="parameter">template</replaceable></option></term>
       <listitem>
diff --git a/src/bin/scripts/createdb.c b/src/bin/scripts/createdb.c
index b0c6805..9d3c4ef 100644
--- a/src/bin/scripts/createdb.c
+++ b/src/bin/scripts/createdb.c
@@ -37,6 +37,7 @@ main(int argc, char *argv[])
 		{"lc-collate", required_argument, NULL, 1},
 		{"lc-ctype", required_argument, NULL, 2},
 		{"locale", required_argument, NULL, 'l'},
+		{"strategy", required_argument, NULL, 'S'},
 		{"maintenance-db", required_argument, NULL, 3},
 		{NULL, 0, NULL, 0}
 	};
@@ -61,6 +62,7 @@ main(int argc, char *argv[])
 	char	   *lc_collate = NULL;
 	char	   *lc_ctype = NULL;
 	char	   *locale = NULL;
+	char	   *strategy = NULL;
 
 	PQExpBufferData sql;
 
@@ -73,7 +75,7 @@ main(int argc, char *argv[])
 
 	handle_help_version_opts(argc, argv, "createdb", help);
 
-	while ((c = getopt_long(argc, argv, "h:p:U:wWeO:D:T:E:l:", long_options, &optindex)) != -1)
+	while ((c = getopt_long(argc, argv, "h:p:U:wWeO:D:T:E:l:S:", long_options, &optindex)) != -1)
 	{
 		switch (c)
 		{
@@ -119,6 +121,9 @@ main(int argc, char *argv[])
 			case 3:
 				maintenance_db = pg_strdup(optarg);
 				break;
+			case 'S':
+				strategy = pg_strdup(optarg);
+				break;
 			default:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname);
 				exit(1);
@@ -217,6 +222,8 @@ main(int argc, char *argv[])
 		appendPQExpBufferStr(&sql, " LC_CTYPE ");
 		appendStringLiteralConn(&sql, lc_ctype, conn);
 	}
+	if (strategy)
+		appendPQExpBuffer(&sql, " STRATEGY %s ", fmtId(strategy));
 
 	appendPQExpBufferChar(&sql, ';');
 
@@ -274,6 +281,7 @@ help(const char *progname)
 	printf(_("      --lc-collate=LOCALE      LC_COLLATE setting for the database\n"));
 	printf(_("      --lc-ctype=LOCALE        LC_CTYPE setting for the database\n"));
 	printf(_("  -O, --owner=OWNER            database user to own the new database\n"));
+	printf(_("  -S, --strategy=STRATEGY      database creation strategy wal_log or file_copy\n"));
 	printf(_("  -T, --template=TEMPLATE      template database to copy\n"));
 	printf(_("  -V, --version                output version information, then exit\n"));
 	printf(_("  -?, --help                   show this help, then exit\n"));
diff --git a/src/bin/scripts/t/020_createdb.pl b/src/bin/scripts/t/020_createdb.pl
index 6392454..ccfbe17 100644
--- a/src/bin/scripts/t/020_createdb.pl
+++ b/src/bin/scripts/t/020_createdb.pl
@@ -76,4 +76,24 @@ $node->command_checks_all(
 	],
 	'createdb with incorrect --lc-ctype');
 
+$node->command_checks_all(
+	[ 'createdb', '--strategy', "foo", 'foobar2' ],
+	1,
+	[qr/^$/],
+	[
+		qr/^createdb: error: database creation failed: ERROR:  invalid create database strategy|^createdb: error: database creation failed: ERROR:  invalid create database strategy foo/s
+	],
+	'createdb with incorrect --strategy');
+
+# Check database creation strategy
+$node->issues_sql_like(
+	[ 'createdb', '-T', 'foobar2', 'foobar4', '-S', 'wal_log'],
+	qr/statement: CREATE DATABASE foobar4 TEMPLATE foobar2 STRATEGY wal_log/,
+	'create database with WAL_LOG strategy');
+
+$node->issues_sql_like(
+	[ 'createdb', '-T', 'foobar2', 'foobar5', '-S', 'file_copy'],
+	qr/statement: CREATE DATABASE foobar5 TEMPLATE foobar2 STRATEGY file_copy/,
+	'create database with FILE_COPY strategy');
+
 done_testing();
-- 
1.8.3.1