At 2004-09-20 13:24:47 -0400, [EMAIL PROTECTED] wrote:
>
> It depends on whether you think that PQprepare should bundle the
> Describe Statement operation or not.
I decided against bundling the two operations together. Here's a patch
to add PQprepare() and PQsendPrepare() in a fairly self-contained way.
Also attached is a test program à la testlibpq3.c that I used to test
the change. This should be all that's needed for DBD::Pg to prepare a
statement without pre-specifying types.
(I'll post a separate patch for PQdescribe() later. It's a little more
involved, and I need to fix a couple of bugs I found during testing.)
Any thoughts? Does this look good enough for 8.0?
-- ams
--- libpq-fe.h.1~ 2004-10-05 18:14:07.885948042 +0530
+++ libpq-fe.h 2004-10-05 22:19:07.544034341 +0530
@@ -292,6 +292,9 @@ extern void PQinitSSL(int do_init);
/* Simple synchronous query */
extern PGresult *PQexec(PGconn *conn, const char *query);
+extern PGresult *PQprepare(PGconn *conn, const char *stmtName,
+ const char *query, int nParams,
+ const Oid *paramTypes);
extern PGresult *PQexecParams(PGconn *conn,
const char *command,
int nParams,
@@ -309,6 +312,9 @@ extern PGresult *PQexecPrepared(PGconn *
int resultFormat);
/* Interface for multiple-result or asynchronous queries */
+extern PGresult *PQsendPrepare(PGconn *conn, const char *stmtName,
+ const char *query, int
nParams,
+ const Oid *paramTypes);
extern int PQsendQuery(PGconn *conn, const char *query);
extern int PQsendQueryParams(PGconn *conn,
const char *command,
--- fe-exec.c.1~ 2004-10-02 06:15:44.000000000 +0530
+++ fe-exec.c 2004-10-05 22:02:03.459149212 +0530
@@ -635,6 +635,69 @@ pqSaveParameterStatus(PGconn *conn, cons
/*
+ * PQsendPrepare
+ * Submit a Parse message, but don't wait for it to finish.
+ *
+ * Returns: 1 if successfully submitted
+ * 0 if error (conn->errorMessage is set)
+ */
+int
+PQsendPrepare(PGconn *conn,
+ const char *stmtName, const char *query,
+ int nParams, const Oid *paramTypes)
+{
+ if (PG_PROTOCOL_MAJOR(conn->pversion) < 3)
+ {
+ printfPQExpBuffer(&conn->errorMessage,
+ libpq_gettext("function requires at
least protocol version 3.0\n"));
+ return 0;
+ }
+
+ if (!PQsendQueryStart(conn))
+ return 0;
+
+ if (pqPutMsgStart('P', false, conn) < 0 ||
+ pqPuts(stmtName, conn) < 0 ||
+ pqPuts(query, conn) < 0)
+ goto sendFailed;
+
+ if (nParams > 0 && paramTypes)
+ {
+ int i;
+
+ if (pqPutInt(nParams, 2, conn) < 0)
+ goto sendFailed;
+ for (i = 0; i < nParams; i++)
+ {
+ if (pqPutInt(paramTypes[i], 4, conn) < 0)
+ goto sendFailed;
+ }
+ }
+ else
+ {
+ if (pqPutInt(0, 2, conn) < 0)
+ goto sendFailed;
+ }
+ if (pqPutMsgEnd(conn) < 0)
+ goto sendFailed;
+
+ if (pqPutMsgStart('S', false, conn) < 0 ||
+ pqPutMsgEnd(conn) < 0)
+ goto sendFailed;
+
+ conn->ext_query = true;
+ if (pqFlush(conn) < 0)
+ goto sendFailed;
+ conn->asyncStatus = PGASYNC_BUSY;
+ return 1;
+
+sendFailed:
+ pqHandleSendFailure(conn);
+ return 0;
+}
+
+
+/*
* PQsendQuery
* Submit a query, but don't wait for it to finish
*
@@ -1145,6 +1208,28 @@ PQexec(PGconn *conn, const char *query)
return PQexecFinish(conn);
}
+
+/*
+ * PQprepare
+ * Creates a prepared statement by issuing a v3.0 parse message.
+ *
+ * Returns NULL if the query failed, and a new PGresult otherwise. The
+ * user is responsible for calling PQclient() on the result.
+ */
+
+PGresult *
+PQprepare(PGconn *conn,
+ const char *stmtName, const char *query,
+ int nParams, const Oid *paramTypes)
+{
+ if (!PQexecStart(conn))
+ return NULL;
+ if (!PQsendPrepare(conn, stmtName, query, nParams, paramTypes))
+ return NULL;
+ return PQexecFinish(conn);
+}
+
+
/*
* PQexecParams
* Like PQexec, but use protocol 3.0 so we can pass parameters
--- fe-protocol3.c.1~ 2004-10-05 18:59:55.293092244 +0530
+++ fe-protocol3.c 2004-10-05 19:17:48.154807848 +0530
@@ -220,6 +220,11 @@ pqParseInput3(PGconn *conn)
conn->asyncStatus = PGASYNC_READY;
break;
case '1': /* Parse Complete */
+ if (conn->result == NULL)
+ conn->result =
PQmakeEmptyPGresult(conn,
+
PGRES_COMMAND_OK);
+ conn->asyncStatus = PGASYNC_READY;
+ break;
case '2': /* Bind Complete */
case '3': /* Close Complete */
/* Nothing to do for these message types */
/*
* Test program for PQprepare/PQdescribe.
* Abhijit Menon-Sen <[EMAIL PROTECTED]>
*
* create table pqtest (a int, b text, c text);
* insert into pqtest (a,b,c) values (1,'foo','bar');
* insert into pqtest (a,b,c) values (1,'foo','baz');
* insert into pqtest (a,b,c) values (2,'foo','barf');
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "libpq-fe.h"
int main(int argc, char *argv[])
{
int i, a, b, c;
PGconn *conn;
PGresult *res;
char *query = "select * from pqtest where a=$1 and b=$2";
const char *values[2];
conn = PQconnectdb("");
if (PQstatus(conn) != CONNECTION_OK) {
fprintf(stderr, "Couldn't connect to the database: %s",
PQerrorMessage(conn));
PQfinish(conn);
exit(-1);
}
res = PQprepare(conn, "prep", query, 0, NULL);
if (PQresultStatus(res) != PGRES_COMMAND_OK) {
fprintf(stderr, "PREPARE failed: %s", PQerrorMessage(conn));
PQclear(res);
PQfinish(conn);
exit(-1);
}
PQclear(res);
values[0] = "1";
values[1] = "foo";
res = PQexecPrepared(conn, "prep", 2, values, NULL, NULL, 0);
if (PQresultStatus(res) != PGRES_TUPLES_OK) {
fprintf(stderr, "EXECUTE failed: %s", PQerrorMessage(conn));
PQclear(res);
PQfinish(conn);
exit(-1);
}
a = PQfnumber(res, "a");
b = PQfnumber(res, "b");
c = PQfnumber(res, "c");
printf("Results:\n");
for(i = 0; i < PQntuples(res); i++) {
char *av = PQgetvalue(res, i, a);
char *bv = PQgetvalue(res, i, b);
char *cv = PQgetvalue(res, i, c);
printf(" (a=%s)(b=%s)(c=%s)\n", av, bv, cv);
}
printf("%d rows\n", i);
PQclear(res);
PQfinish(conn);
return 0;
}
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