0002-Remove-synchronous-prepare-from-pgbench.patch

From 4e4379a852f1f8f24cead5b3a5e7b90ae9cdac56 Mon Sep 17 00:00:00 2001
From: Dmitrii Bondar <d.bondar@postgrespro.ru>
Date: Mon, 2 Mar 2026 18:08:30 +0700
Subject: [PATCH 2/2] Remove synchronous prepare from pgbench

Pgbench waits for the result of a prepare packet synchronously
when the prepared protocol flag is provided. For this reason
it is impossible to use it with some poolers (such as PgBouncer)
in the session pooling mode.
It is replaced by the full sequence of parse/bind/execute/sync
packets. This behaviour is similar to pgbench with the extended
protocol flag.
---
 doc/src/sgml/libpq.sgml                      | 30 +++++++++++++
 src/bin/pgbench/pgbench.c                    | 22 ++++++++--
 src/bin/pgbench/t/001_pgbench_with_server.pl |  1 -
 src/interfaces/libpq/exports.txt             |  1 +
 src/interfaces/libpq/fe-exec.c               | 46 ++++++++++++++++++++
 src/interfaces/libpq/libpq-fe.h              |  9 ++++
 6 files changed, 104 insertions(+), 5 deletions(-)

diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index e08d46782cc..1cd9c3558a4 100644
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -5329,6 +5329,7 @@ unsigned char *PQunescapeBytea(const unsigned char *from, size_t *to_length);
    <xref linkend="libpq-PQsendQueryParams"/>,
    <xref linkend="libpq-PQsendPrepare"/>,
    <xref linkend="libpq-PQsendQueryPrepared"/>,
+   <xref linkend="libpq-PQsendPBES"/>,
    <xref linkend="libpq-PQsendDescribePrepared"/>,
    <xref linkend="libpq-PQsendDescribePortal"/>,
    <xref linkend="libpq-PQsendClosePrepared"/>, and
@@ -5450,6 +5451,34 @@ int PQsendQueryPrepared(PGconn *conn,
      </listitem>
     </varlistentry>
 
+    <varlistentry id="libpq-PQsendPBES">
+     <term><function>PQsendPBES</function><indexterm><primary>PQsendPBES</primary></indexterm></term>
+
+     <listitem>
+      <para>
+       Sends a request to prepare and execute a statement with given
+       parameters, without waiting for the result(s).
+<synopsis>
+int PQsendPBES(PGconn *conn,
+               const char *stmtName,
+               const char *query,
+               int nParams,
+               const Oid *paramTypes,
+               const char *const *paramValues,
+               const int *paramLengths,
+               const int *paramFormats,
+               int resultFormat);
+</synopsis>
+
+       This is similar to <xref linkend="libpq-PQsendQueryPrepared"/>, but the
+       statement is prepared as part of the same request using the supplied
+       query string. Internally, it sends a Parse, Bind, Execute, and Sync
+       message sequence. The function's parameters are handled identically to
+       <xref linkend="libpq-PQexecParams"/>.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry id="libpq-PQsendDescribePrepared">
      <term><function>PQsendDescribePrepared</function><indexterm><primary>PQsendDescribePrepared</primary></indexterm></term>
 
@@ -5540,6 +5569,7 @@ int PQsendClosePortal(PGconn *conn, const char *portalName);
        <xref linkend="libpq-PQsendQueryParams"/>,
        <xref linkend="libpq-PQsendPrepare"/>,
        <xref linkend="libpq-PQsendQueryPrepared"/>,
+       <xref linkend="libpq-PQsendPBES"/>,
        <xref linkend="libpq-PQsendDescribePrepared"/>,
        <xref linkend="libpq-PQsendDescribePortal"/>,
        <xref linkend="libpq-PQsendClosePrepared"/>,
diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c
index 1dae918cc09..749b9347a6e 100644
--- a/src/bin/pgbench/pgbench.c
+++ b/src/bin/pgbench/pgbench.c
@@ -3179,12 +3179,26 @@ sendCommand(CState *st, Command *command)
 	{
 		const char *params[MAX_ARGS];
 
-		prepareCommand(st, st->command);
 		getQueryParams(&st->variables, command, params);
 
-		pg_log_debug("client %d sending %s", st->id, command->prepname);
-		r = PQsendQueryPrepared(st->con, command->prepname, command->argc - 1,
-								params, NULL, NULL, 0);
+		if (!st->prepared)
+			allocCStatePrepared(st);
+
+		if (!st->prepared[st->use_file][st->command])
+		{
+			r = PQsendPBES(st->con, command->prepname,
+						   command->argv[0], command->argc - 1, NULL,
+						   params, NULL, NULL, 0);
+			if (!r)
+				pg_log_error("%s", PQerrorMessage(st->con));
+			st->prepared[st->use_file][st->command] = true;
+		}
+		else
+		{
+			pg_log_debug("client %d sending %s", st->id, command->prepname);
+			r = PQsendQueryPrepared(st->con, command->prepname, command->argc - 1,
+									params, NULL, NULL, 0);
+		}
 	}
 	else						/* unknown sql mode */
 		r = 0;
diff --git a/src/bin/pgbench/t/001_pgbench_with_server.pl b/src/bin/pgbench/t/001_pgbench_with_server.pl
index b7685ea5d20..c047b5d0460 100644
--- a/src/bin/pgbench/t/001_pgbench_with_server.pl
+++ b/src/bin/pgbench/t/001_pgbench_with_server.pl
@@ -1231,7 +1231,6 @@ my @errors = (
 		2,
 		[
 			qr{ERROR:  syntax error},
-			qr{prepared statement .* does not exist}
 		],
 		q{-- SQL syntax error
     SELECT 1 + ;
diff --git a/src/interfaces/libpq/exports.txt b/src/interfaces/libpq/exports.txt
index dbbae642d76..7f6664319d7 100644
--- a/src/interfaces/libpq/exports.txt
+++ b/src/interfaces/libpq/exports.txt
@@ -210,3 +210,4 @@ PQgetAuthDataHook         207
 PQdefaultAuthDataHook     208
 PQfullProtocolVersion     209
 appendPQExpBufferVA       210
+PQsendPBES                211
\ No newline at end of file
diff --git a/src/interfaces/libpq/fe-exec.c b/src/interfaces/libpq/fe-exec.c
index 203d388bdbf..19e4381e6bb 100644
--- a/src/interfaces/libpq/fe-exec.c
+++ b/src/interfaces/libpq/fe-exec.c
@@ -1682,6 +1682,52 @@ PQsendQueryPrepared(PGconn *conn,
 						   resultFormat);
 }
 
+/* PQsendPBES
+ *		Like PQsendQueryPrepared, but it also prepares a query
+ */
+int
+PQsendPBES(PGconn *conn,
+		   const char *stmtName,
+		   const char *query,
+		   int nParams,
+		   const Oid *paramTypes,
+		   const char *const *paramValues,
+		   const int *paramLengths,
+		   const int *paramFormats,
+		   int resultFormat)
+{
+	if (!PQsendQueryStart(conn, true))
+		return 0;
+
+	/* check the arguments */
+	if (!stmtName)
+	{
+		libpq_append_conn_error(conn, "statement name is a null pointer");
+		return 0;
+	}
+	if (!query)
+	{
+		libpq_append_conn_error(conn, "command string is a null pointer");
+		return 0;
+	}
+	if (nParams < 0 || nParams > PQ_QUERY_PARAM_MAX_LIMIT)
+	{
+		libpq_append_conn_error(conn, "number of parameters must be between 0 and %d",
+								PQ_QUERY_PARAM_MAX_LIMIT);
+		return 0;
+	}
+
+	return PQsendQueryGuts(conn,
+						   query,
+						   stmtName,
+						   nParams,
+						   paramTypes,
+						   paramValues,
+						   paramLengths,
+						   paramFormats,
+						   resultFormat);
+}
+
 /*
  * PQsendQueryStart
  *	Common startup code for PQsendQuery and sibling routines
diff --git a/src/interfaces/libpq/libpq-fe.h b/src/interfaces/libpq/libpq-fe.h
index 905f2f33ab8..772583dcea9 100644
--- a/src/interfaces/libpq/libpq-fe.h
+++ b/src/interfaces/libpq/libpq-fe.h
@@ -525,6 +525,15 @@ extern int	PQsendQueryPrepared(PGconn *conn,
 								const int *paramLengths,
 								const int *paramFormats,
 								int resultFormat);
+extern int	PQsendPBES(PGconn *conn,
+					   const char *stmtName,
+					   const char *query,
+					   int nParams,
+					   const Oid *paramTypes,
+					   const char *const *paramValues,
+					   const int *paramLengths,
+					   const int *paramFormats,
+					   int resultFormat);
 extern int	PQsetSingleRowMode(PGconn *conn);
 extern int	PQsetChunkedRowsMode(PGconn *conn, int chunkSize);
 extern PGresult *PQgetResult(PGconn *conn);
-- 
2.52.0