Allow publishing the tables of schema.

A new option "FOR ALL TABLES IN SCHEMA" in Create/Alter Publication allows
one or more schemas to be specified, whose tables are selected by the
publisher for sending the data to the subscriber.

The new syntax allows specifying both the tables and schemas. For example:
CREATE PUBLICATION pub1 FOR TABLE t1,t2,t3, ALL TABLES IN SCHEMA s1,s2;
OR
ALTER PUBLICATION pub1 ADD TABLE t1,t2,t3, ALL TABLES IN SCHEMA s1,s2;

A new system table "pg_publication_namespace" has been added, to maintain
the schemas that the user wants to publish through the publication.
Modified the output plugin (pgoutput) to publish the changes if the
relation is part of schema publication.

Updates pg_dump to identify and dump schema publications. Updates the \d
family of commands to display schema publications and \dRp+ variant will
now display associated schemas if any.

Author: Vignesh C, Hou Zhijie, Amit Kapila
Syntax-Suggested-by: Tom Lane, Alvaro Herrera
Reviewed-by: Greg Nancarrow, Masahiko Sawada, Hou Zhijie, Amit Kapila, Haiying Tang, Ajin Cherian, Rahila Syed, Bharath Rupireddy, Mark Dilger
Tested-by: Haiying Tang
Discussion: https://www.postgresql.org/message-id/CALDaNm0OANxuJ6RXqwZsM1MSY4s19nuH3734j4a72etDwvBETQ@mail.gmail.com

1 files changed, 159 insertions, 39 deletions

diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c
index ea4ca5c05c2..006661412ea 100644
--- a/src/bin/psql/describe.c
+++ b/src/bin/psql/describe.c
@@ -3146,17 +3146,40 @@ describeOneTableDetails(const char *schemaname,
 		/* print any publications */
 		if (pset.sversion >= 100000)
 		{
-			printfPQExpBuffer(&buf,
-							  "SELECT pubname\n"
-							  "FROM pg_catalog.pg_publication p\n"
-							  "JOIN pg_catalog.pg_publication_rel pr ON p.oid = pr.prpubid\n"
-							  "WHERE pr.prrelid = '%s'\n"
-							  "UNION ALL\n"
-							  "SELECT pubname\n"
-							  "FROM pg_catalog.pg_publication p\n"
-							  "WHERE p.puballtables AND pg_catalog.pg_relation_is_publishable('%s')\n"
-							  "ORDER BY 1;",
-							  oid, oid);
+			if (pset.sversion >= 150000)
+			{
+				printfPQExpBuffer(&buf,
+								  "SELECT pubname\n"
+								  "FROM pg_catalog.pg_publication p\n"
+								  "		JOIN pg_catalog.pg_publication_namespace pn ON p.oid = pn.pnpubid\n"
+								  "		JOIN pg_catalog.pg_class pc ON pc.relnamespace = pn.pnnspid\n"
+								  "WHERE pc.oid ='%s' and pg_catalog.pg_relation_is_publishable('%s')\n"
+								  "UNION\n"
+								  "SELECT pubname\n"
+								  "FROM pg_catalog.pg_publication p\n"
+								  "		JOIN pg_catalog.pg_publication_rel pr ON p.oid = pr.prpubid\n"
+								  "WHERE pr.prrelid = '%s'\n"
+								  "UNION\n"
+								  "SELECT pubname\n"
+								  "FROM pg_catalog.pg_publication p\n"
+								  "WHERE puballtables AND pg_catalog.pg_relation_is_publishable('%s')\n"
+								  "ORDER BY 1;",
+								  oid, oid, oid, oid);
+			}
+			else
+			{
+				printfPQExpBuffer(&buf,
+								  "SELECT pubname\n"
+								  "FROM pg_catalog.pg_publication p\n"
+								  "JOIN pg_catalog.pg_publication_rel pr ON p.oid = pr.prpubid\n"
+								  "WHERE pr.prrelid = '%s'\n"
+								  "UNION ALL\n"
+								  "SELECT pubname\n"
+								  "FROM pg_catalog.pg_publication p\n"
+								  "WHERE p.puballtables AND pg_catalog.pg_relation_is_publishable('%s')\n"
+								  "ORDER BY 1;",
+								  oid, oid);
+			}
 
 			result = PSQLexec(buf.data);
 			if (!result)
@@ -5020,6 +5043,8 @@ listSchemas(const char *pattern, bool verbose, bool showSystem)
 	PQExpBufferData buf;
 	PGresult   *res;
 	printQueryOpt myopt = pset.popt;
+	int			pub_schema_tuples = 0;
+	char	  **footers = NULL;
 
 	initPQExpBuffer(&buf);
 	printfPQExpBuffer(&buf,
@@ -5052,17 +5077,80 @@ listSchemas(const char *pattern, bool verbose, bool showSystem)
 	appendPQExpBufferStr(&buf, "ORDER BY 1;");
 
 	res = PSQLexec(buf.data);
-	termPQExpBuffer(&buf);
 	if (!res)
+	{
+		termPQExpBuffer(&buf);
 		return false;
+	}
 
 	myopt.nullPrint = NULL;
 	myopt.title = _("List of schemas");
 	myopt.translate_header = true;
 
+	if (pattern && pset.sversion >= 150000)
+	{
+		PGresult   *result;
+		int			i;
+
+		printfPQExpBuffer(&buf,
+						  "SELECT pubname \n"
+						  "FROM pg_catalog.pg_publication p\n"
+						  "		JOIN pg_catalog.pg_publication_namespace pn ON p.oid = pn.pnpubid\n"
+						  "		JOIN pg_catalog.pg_namespace n ON n.oid = pn.pnnspid \n"
+						  "WHERE n.nspname = '%s'\n"
+						  "ORDER BY 1",
+						  pattern);
+		result = PSQLexec(buf.data);
+		if (!result)
+		{
+			termPQExpBuffer(&buf);
+			return false;
+		}
+		else
+			pub_schema_tuples = PQntuples(result);
+
+		if (pub_schema_tuples > 0)
+		{
+			/*
+			 * Allocate memory for footers. Size of footers will be 1 (for
+			 * storing "Publications:" string) + publication schema mapping
+			 * count +  1 (for storing NULL).
+			 */
+			footers = (char **) pg_malloc((1 + pub_schema_tuples + 1) * sizeof(char *));
+			footers[0] = pg_strdup(_("Publications:"));
+
+			/* Might be an empty set - that's ok */
+			for (i = 0; i < pub_schema_tuples; i++)
+			{
+				printfPQExpBuffer(&buf, "    \"%s\"",
+								  PQgetvalue(result, i, 0));
+
+				footers[i + 1] = pg_strdup(buf.data);
+			}
+
+			footers[i + 1] = NULL;
+			myopt.footers = footers;
+		}
+
+		PQclear(result);
+	}
+
 	printQuery(res, &myopt, pset.queryFout, false, pset.logfile);
 
+	termPQExpBuffer(&buf);
 	PQclear(res);
+
+	/* Free the memory allocated for the footer */
+	if (footers)
+	{
+		char	  **footer = NULL;
+
+		for (footer = footers; *footer; footer++)
+			pg_free(*footer);
+
+		pg_free(footers);
+	}
+
 	return true;
 }
 
@@ -6210,6 +6298,41 @@ listPublications(const char *pattern)
 }
 
 /*
+ * Add footer to publication description.
+ */
+static bool
+addFooterToPublicationDesc(PQExpBuffer buf, char *footermsg,
+						   bool singlecol, printTableContent *cont)
+{
+	PGresult   *res;
+	int			count = 0;
+	int			i = 0;
+
+	res = PSQLexec(buf->data);
+	if (!res)
+		return false;
+	else
+		count = PQntuples(res);
+
+	if (count > 0)
+		printTableAddFooter(cont, _(footermsg));
+
+	for (i = 0; i < count; i++)
+	{
+		if (!singlecol)
+			printfPQExpBuffer(buf, "    \"%s.%s\"", PQgetvalue(res, i, 0),
+							  PQgetvalue(res, i, 1));
+		else
+			printfPQExpBuffer(buf, "    \"%s\"", PQgetvalue(res, i, 0));
+
+		printTableAddFooter(cont, buf->data);
+	}
+
+	PQclear(res);
+	return true;
+}
+
+/*
  * \dRp+
  * Describes publications including the contents.
  *
@@ -6224,6 +6347,9 @@ describePublications(const char *pattern)
 	bool		has_pubtruncate;
 	bool		has_pubviaroot;
 
+	PQExpBufferData title;
+	printTableContent cont;
+
 	if (pset.sversion < 100000)
 	{
 		char		sverbuf[32];
@@ -6286,15 +6412,10 @@ describePublications(const char *pattern)
 		const char	align = 'l';
 		int			ncols = 5;
 		int			nrows = 1;
-		int			tables = 0;
-		PGresult   *tabres;
 		char	   *pubid = PQgetvalue(res, i, 0);
 		char	   *pubname = PQgetvalue(res, i, 1);
 		bool		puballtables = strcmp(PQgetvalue(res, i, 3), "t") == 0;
-		int			j;
-		PQExpBufferData title;
 		printTableOpt myopt = pset.popt.topt;
-		printTableContent cont;
 
 		if (has_pubtruncate)
 			ncols++;
@@ -6327,6 +6448,7 @@ describePublications(const char *pattern)
 
 		if (!puballtables)
 		{
+			/* Get the tables for the specified publication */
 			printfPQExpBuffer(&buf,
 							  "SELECT n.nspname, c.relname\n"
 							  "FROM pg_catalog.pg_class c,\n"
@@ -6336,31 +6458,22 @@ describePublications(const char *pattern)
 							  "  AND c.oid = pr.prrelid\n"
 							  "  AND pr.prpubid = '%s'\n"
 							  "ORDER BY 1,2", pubid);
+			if (!addFooterToPublicationDesc(&buf, "Tables:", false, &cont))
+				goto error_return;
 
-			tabres = PSQLexec(buf.data);
-			if (!tabres)
-			{
-				printTableCleanup(&cont);
-				PQclear(res);
-				termPQExpBuffer(&buf);
-				termPQExpBuffer(&title);
-				return false;
-			}
-			else
-				tables = PQntuples(tabres);
-
-			if (tables > 0)
-				printTableAddFooter(&cont, _("Tables:"));
-
-			for (j = 0; j < tables; j++)
+			if (pset.sversion >= 150000)
 			{
-				printfPQExpBuffer(&buf, "    \"%s.%s\"",
-								  PQgetvalue(tabres, j, 0),
-								  PQgetvalue(tabres, j, 1));
-
-				printTableAddFooter(&cont, buf.data);
+				/* Get the schemas for the specified publication */
+				printfPQExpBuffer(&buf,
+								  "SELECT n.nspname\n"
+								  "FROM pg_catalog.pg_namespace n\n"
+								  "     JOIN pg_catalog.pg_publication_namespace pn ON n.oid = pn.pnnspid\n"
+								  "WHERE pn.pnpubid = '%s'\n"
+								  "ORDER BY 1", pubid);
+				if (!addFooterToPublicationDesc(&buf, "Tables from schemas:",
+												true, &cont))
+					goto error_return;
 			}
-			PQclear(tabres);
 		}
 
 		printTable(&cont, pset.queryFout, false, pset.logfile);
@@ -6373,6 +6486,13 @@ describePublications(const char *pattern)
 	PQclear(res);
 
 	return true;
+
+error_return:
+	printTableCleanup(&cont);
+	PQclear(res);
+	termPQExpBuffer(&buf);
+	termPQExpBuffer(&title);
+	return false;
 }
 
 /*