postgresql/contrib/vacuumlo/vacuumlo.c
1999-05-25 16:15:34 +00:00

212 lines
4.3 KiB
C

/*-------------------------------------------------------------------------
*
* vacuumlo.c
* This removes orphaned large objects from a database.
*
* Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/contrib/vacuumlo/vacuumlo.c,v 1.2 1999/05/25 16:06:31 momjian Exp $
*
*-------------------------------------------------------------------------
*/
#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include "libpq-fe.h"
#include "libpq/libpq-fs.h"
#define BUFSIZE 1024
int vacuumlo(char *, int);
/*
* This vacuums a database. It returns 1 on success, -1 on failure.
*/
int
vacuumlo(char *database, int verbose)
{
PGconn *conn;
PGresult *res,
*res2;
char buf[BUFSIZE];
int matched = 0; /* Number matched per scan */
int i;
conn = PQsetdb(NULL, NULL, NULL, NULL, database);
/* check to see that the backend connection was successfully made */
if (PQstatus(conn) == CONNECTION_BAD)
{
fprintf(stderr, "Connection to database '%s' failed.\n", database);
fprintf(stderr, "%s", PQerrorMessage(conn));
return -1;
}
if (verbose)
fprintf(stdout, "Connected to %s\n", database);
/*
* First we create and populate the lo temp table
*/
buf[0] = '\0';
strcat(buf, "SELECT oid AS lo ");
strcat(buf, "INTO TEMP TABLE vacuum_l ");
strcat(buf, "FROM pg_class ");
strcat(buf, "WHERE relkind='l'");
if (!(res = PQexec(conn, buf)))
{
fprintf(stderr, "Failed to create temp table.\n");
PQfinish(conn);
return -1;
}
PQclear(res);
/*
* Now find any candidate tables who have columns of type oid (the
* column oid is ignored, as it has attnum < 1)
*/
buf[0] = '\0';
strcat(buf, "SELECT c.relname, a.attname ");
strcat(buf, "FROM pg_class c, pg_attribute a, pg_type t ");
strcat(buf, "WHERE a.attnum > 0 ");
strcat(buf, " AND a.attrelid = c.oid ");
strcat(buf, " AND a.atttypid = t.oid ");
strcat(buf, " AND t.typname = 'oid' ");
strcat(buf, " AND c.relname NOT LIKE 'pg_%'");
if (!(res = PQexec(conn, buf)))
{
fprintf(stderr, "Failed to create temp table.\n");
PQfinish(conn);
return -1;
}
for (i = 0; i < PQntuples(res); i++)
{
char *table,
*field;
table = PQgetvalue(res, i, 0);
field = PQgetvalue(res, i, 1);
if (verbose)
{
fprintf(stdout, "Checking %s in %s: ", field, table);
fflush(stdout);
}
res2 = PQexec(conn, "begin");
PQclear(res2);
buf[0] = '\0';
strcat(buf, "DELETE FROM vacuum_l ");
strcat(buf, "WHERE lo IN (");
strcat(buf, "SELECT ");
strcat(buf, field);
strcat(buf, " FROM ");
strcat(buf, table);
strcat(buf, ");");
if (!(res2 = PQexec(conn, buf)))
{
fprintf(stderr, "Failed to check %s in table %s\n", field, table);
PQclear(res);
PQfinish(conn);
return -1;
}
if (PQresultStatus(res2) != PGRES_COMMAND_OK)
{
fprintf(stderr,
"Failed to check %s in table %s\n%s\n",
field, table,
PQerrorMessage(conn)
);
PQclear(res2);
PQclear(res);
PQfinish(conn);
return -1;
}
PQclear(res2);
res2 = PQexec(conn, "end");
PQclear(res2);
}
PQclear(res);
/* Start the transaction */
res = PQexec(conn, "begin");
PQclear(res);
/*
* Finally, those entries remaining in vacuum_l are orphans.
*/
buf[0] = '\0';
strcat(buf, "SELECT lo ");
strcat(buf, "FROM vacuum_l");
if (!(res = PQexec(conn, buf)))
{
fprintf(stderr, "Failed to read temp table.\n");
PQfinish(conn);
return -1;
}
matched = PQntuples(res);
for (i = 0; i < matched; i++)
{
Oid lo = (Oid) atoi(PQgetvalue(res, i, 0));
if (verbose)
{
fprintf(stdout, "\rRemoving lo %6d \n", lo);
fflush(stdout);
}
if (lo_unlink(conn, lo) < 0)
fprintf(stderr, "Failed to remove lo %d\n", lo);
}
PQclear(res);
/*
* That's all folks!
*/
res = PQexec(conn, "end");
PQclear(res);
PQfinish(conn);
if (verbose)
fprintf(stdout, "\rRemoved %d large objects from %s.\n", matched, database);
return 0;
}
int
main(int argc, char **argv)
{
int verbose = 0;
int arg;
int rc = 0;
if (argc < 2)
{
fprintf(stderr, "Usage: %s [-v] database_name [db2 ... dbn]\n",
argv[0]);
exit(1);
}
for (arg = 1; arg < argc; arg++)
{
if (strcmp("-v", argv[arg]) == 0)
verbose = !verbose;
else
rc += vacuumlo(argv[arg], verbose);
}
return rc;
}