postgresql/contrib/findoidjoins/findoidjoins.c
2004-08-29 04:13:13 +00:00

148 lines
3.6 KiB
C

/*
* findoidjoins.c
*
* Copyright (c) 2002-2004, PostgreSQL Global Development Group
*
* $PostgreSQL: pgsql/contrib/findoidjoins/findoidjoins.c,v 1.24 2004/08/29 04:12:16 momjian Exp $
*/
#include "postgres_fe.h"
#include "libpq-fe.h"
#include "pqexpbuffer.h"
int
main(int argc, char **argv)
{
PGconn *conn;
PQExpBufferData sql;
PGresult *res;
PGresult *pkrel_res;
PGresult *fkrel_res;
char *fk_relname;
char *fk_nspname;
char *fk_attname;
char *pk_relname;
char *pk_nspname;
int fk,
pk; /* loop counters */
if (argc != 2)
{
fprintf(stderr, "Usage: %s database\n", argv[0]);
exit(EXIT_FAILURE);
}
initPQExpBuffer(&sql);
appendPQExpBuffer(&sql, "dbname=%s", argv[1]);
conn = PQconnectdb(sql.data);
if (PQstatus(conn) == CONNECTION_BAD)
{
fprintf(stderr, "connection error: %s\n", PQerrorMessage(conn));
exit(EXIT_FAILURE);
}
/* Get a list of relations that have OIDs */
resetPQExpBuffer(&sql);
appendPQExpBuffer(&sql, "%s",
"SET search_path = public;"
"SELECT c.relname, (SELECT nspname FROM "
"pg_catalog.pg_namespace n WHERE n.oid = c.relnamespace) AS nspname "
"FROM pg_catalog.pg_class c "
"WHERE c.relkind = 'r' "
"AND c.relhasoids "
"ORDER BY nspname, c.relname"
);
res = PQexec(conn, sql.data);
if (!res || PQresultStatus(res) != PGRES_TUPLES_OK)
{
fprintf(stderr, "sql error: %s\n", PQerrorMessage(conn));
exit(EXIT_FAILURE);
}
pkrel_res = res;
/* Get a list of columns of OID type (or any OID-alias type) */
resetPQExpBuffer(&sql);
appendPQExpBuffer(&sql, "%s",
"SELECT c.relname, "
"(SELECT nspname FROM pg_catalog.pg_namespace n WHERE n.oid = c.relnamespace) AS nspname, "
"a.attname "
"FROM pg_catalog.pg_class c, pg_catalog.pg_attribute a "
"WHERE a.attnum > 0 AND c.relkind = 'r' "
"AND a.attrelid = c.oid "
"AND a.atttypid IN ('pg_catalog.oid'::regtype, "
" 'pg_catalog.regclass'::regtype, "
" 'pg_catalog.regoper'::regtype, "
" 'pg_catalog.regoperator'::regtype, "
" 'pg_catalog.regproc'::regtype, "
" 'pg_catalog.regprocedure'::regtype, "
" 'pg_catalog.regtype'::regtype) "
"ORDER BY nspname, c.relname, a.attnum"
);
res = PQexec(conn, sql.data);
if (!res || PQresultStatus(res) != PGRES_TUPLES_OK)
{
fprintf(stderr, "sql error: %s\n", PQerrorMessage(conn));
exit(EXIT_FAILURE);
}
fkrel_res = res;
/*
* For each column and each relation-having-OIDs, look to see if the
* column contains any values matching entries in the relation.
*/
for (fk = 0; fk < PQntuples(fkrel_res); fk++)
{
fk_relname = PQgetvalue(fkrel_res, fk, 0);
fk_nspname = PQgetvalue(fkrel_res, fk, 1);
fk_attname = PQgetvalue(fkrel_res, fk, 2);
for (pk = 0; pk < PQntuples(pkrel_res); pk++)
{
pk_relname = PQgetvalue(pkrel_res, pk, 0);
pk_nspname = PQgetvalue(pkrel_res, pk, 1);
resetPQExpBuffer(&sql);
appendPQExpBuffer(&sql,
"SELECT 1 "
"FROM \"%s\".\"%s\" t1, "
"\"%s\".\"%s\" t2 "
"WHERE t1.\"%s\"::pg_catalog.oid = t2.oid "
"LIMIT 1",
fk_nspname, fk_relname, pk_nspname, pk_relname, fk_attname);
res = PQexec(conn, sql.data);
if (!res || PQresultStatus(res) != PGRES_TUPLES_OK)
{
fprintf(stderr, "sql error: %s\n", PQerrorMessage(conn));
exit(EXIT_FAILURE);
}
if (PQntuples(res) != 0)
printf("Join %s.%s.%s => %s.%s.oid\n",
fk_nspname, fk_relname, fk_attname,
pk_nspname, pk_relname);
PQclear(res);
}
}
PQclear(pkrel_res);
PQclear(fkrel_res);
PQfinish(conn);
termPQExpBuffer(&sql);
exit(EXIT_SUCCESS);
}