PostgreSQL Source Code  git master
vacuumlo.c
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1 /*-------------------------------------------------------------------------
2  *
3  * vacuumlo.c
4  * This removes orphaned large objects from a database.
5  *
6  * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  *
10  * IDENTIFICATION
11  * contrib/vacuumlo/vacuumlo.c
12  *
13  *-------------------------------------------------------------------------
14  */
15 #include "postgres_fe.h"
16 
17 #include <sys/stat.h>
18 #include <fcntl.h>
19 #include <unistd.h>
20 #ifdef HAVE_TERMIOS_H
21 #include <termios.h>
22 #endif
23 
24 #include "catalog/pg_class_d.h"
25 #include "common/connect.h"
26 #include "common/logging.h"
27 #include "common/string.h"
28 #include "getopt_long.h"
29 #include "libpq-fe.h"
30 #include "pg_getopt.h"
31 
32 #define BUFSIZE 1024
33 
35 {
38  TRI_YES
39 };
40 
41 struct _param
42 {
43  char *pg_user;
44  enum trivalue pg_prompt;
45  char *pg_port;
46  char *pg_host;
47  const char *progname;
48  int verbose;
49  int dry_run;
51 };
52 
53 static int vacuumlo(const char *database, const struct _param *param);
54 static void usage(const char *progname);
55 
56 
57 
58 /*
59  * This vacuums LOs of one database. It returns 0 on success, -1 on failure.
60  */
61 static int
62 vacuumlo(const char *database, const struct _param *param)
63 {
64  PGconn *conn;
65  PGresult *res,
66  *res2;
67  char buf[BUFSIZE];
68  long matched;
69  long deleted;
70  int i;
71  bool new_pass;
72  bool success = true;
73  static char *password = NULL;
74 
75  /* Note: password can be carried over from a previous call */
76  if (param->pg_prompt == TRI_YES && !password)
77  password = simple_prompt("Password: ", false);
78 
79  /*
80  * Start the connection. Loop until we have a password if requested by
81  * backend.
82  */
83  do
84  {
85 #define PARAMS_ARRAY_SIZE 7
86 
87  const char *keywords[PARAMS_ARRAY_SIZE];
88  const char *values[PARAMS_ARRAY_SIZE];
89 
90  keywords[0] = "host";
91  values[0] = param->pg_host;
92  keywords[1] = "port";
93  values[1] = param->pg_port;
94  keywords[2] = "user";
95  values[2] = param->pg_user;
96  keywords[3] = "password";
97  values[3] = password;
98  keywords[4] = "dbname";
99  values[4] = database;
100  keywords[5] = "fallback_application_name";
101  values[5] = param->progname;
102  keywords[6] = NULL;
103  values[6] = NULL;
104 
105  new_pass = false;
106  conn = PQconnectdbParams(keywords, values, true);
107  if (!conn)
108  {
109  pg_log_error("connection to database \"%s\" failed", database);
110  return -1;
111  }
112 
113  if (PQstatus(conn) == CONNECTION_BAD &&
115  !password &&
116  param->pg_prompt != TRI_NO)
117  {
118  PQfinish(conn);
119  password = simple_prompt("Password: ", false);
120  new_pass = true;
121  }
122  } while (new_pass);
123 
124  /* check to see that the backend connection was successfully made */
125  if (PQstatus(conn) == CONNECTION_BAD)
126  {
128  PQfinish(conn);
129  return -1;
130  }
131 
132  if (param->verbose)
133  {
134  fprintf(stdout, "Connected to database \"%s\"\n", database);
135  if (param->dry_run)
136  fprintf(stdout, "Test run: no large objects will be removed!\n");
137  }
138 
141  {
142  pg_log_error("failed to set search_path: %s", PQerrorMessage(conn));
143  PQclear(res);
144  PQfinish(conn);
145  return -1;
146  }
147  PQclear(res);
148 
149  /*
150  * First we create and populate the LO temp table
151  */
152  buf[0] = '\0';
153  strcat(buf, "CREATE TEMP TABLE vacuum_l AS ");
154  if (PQserverVersion(conn) >= 90000)
155  strcat(buf, "SELECT oid AS lo FROM pg_largeobject_metadata");
156  else
157  strcat(buf, "SELECT DISTINCT loid AS lo FROM pg_largeobject");
158  res = PQexec(conn, buf);
160  {
161  pg_log_error("failed to create temp table: %s", PQerrorMessage(conn));
162  PQclear(res);
163  PQfinish(conn);
164  return -1;
165  }
166  PQclear(res);
167 
168  /*
169  * Analyze the temp table so that planner will generate decent plans for
170  * the DELETEs below.
171  */
172  buf[0] = '\0';
173  strcat(buf, "ANALYZE vacuum_l");
174  res = PQexec(conn, buf);
176  {
177  pg_log_error("failed to vacuum temp table: %s", PQerrorMessage(conn));
178  PQclear(res);
179  PQfinish(conn);
180  return -1;
181  }
182  PQclear(res);
183 
184  /*
185  * Now find any candidate tables that have columns of type oid.
186  *
187  * NOTE: we ignore system tables and temp tables by the expedient of
188  * rejecting tables in schemas named 'pg_*'. In particular, the temp
189  * table formed above is ignored, and pg_largeobject will be too. If
190  * either of these were scanned, obviously we'd end up with nothing to
191  * delete...
192  */
193  buf[0] = '\0';
194  strcat(buf, "SELECT s.nspname, c.relname, a.attname ");
195  strcat(buf, "FROM pg_class c, pg_attribute a, pg_namespace s, pg_type t ");
196  strcat(buf, "WHERE a.attnum > 0 AND NOT a.attisdropped ");
197  strcat(buf, " AND a.attrelid = c.oid ");
198  strcat(buf, " AND a.atttypid = t.oid ");
199  strcat(buf, " AND c.relnamespace = s.oid ");
200  strcat(buf, " AND t.typname in ('oid', 'lo') ");
201  strcat(buf, " AND c.relkind in (" CppAsString2(RELKIND_RELATION) ", " CppAsString2(RELKIND_MATVIEW) ")");
202  strcat(buf, " AND s.nspname !~ '^pg_'");
203  res = PQexec(conn, buf);
205  {
206  pg_log_error("failed to find OID columns: %s", PQerrorMessage(conn));
207  PQclear(res);
208  PQfinish(conn);
209  return -1;
210  }
211 
212  for (i = 0; i < PQntuples(res); i++)
213  {
214  char *schema,
215  *table,
216  *field;
217 
218  schema = PQgetvalue(res, i, 0);
219  table = PQgetvalue(res, i, 1);
220  field = PQgetvalue(res, i, 2);
221 
222  if (param->verbose)
223  fprintf(stdout, "Checking %s in %s.%s\n", field, schema, table);
224 
225  schema = PQescapeIdentifier(conn, schema, strlen(schema));
226  table = PQescapeIdentifier(conn, table, strlen(table));
227  field = PQescapeIdentifier(conn, field, strlen(field));
228 
229  if (!schema || !table || !field)
230  {
232  PQclear(res);
233  PQfinish(conn);
234  PQfreemem(schema);
235  PQfreemem(table);
236  PQfreemem(field);
237  return -1;
238  }
239 
241  "DELETE FROM vacuum_l "
242  "WHERE lo IN (SELECT %s FROM %s.%s)",
243  field, schema, table);
244  res2 = PQexec(conn, buf);
245  if (PQresultStatus(res2) != PGRES_COMMAND_OK)
246  {
247  pg_log_error("failed to check %s in table %s.%s: %s",
248  field, schema, table, PQerrorMessage(conn));
249  PQclear(res2);
250  PQclear(res);
251  PQfinish(conn);
252  PQfreemem(schema);
253  PQfreemem(table);
254  PQfreemem(field);
255  return -1;
256  }
257  PQclear(res2);
258 
259  PQfreemem(schema);
260  PQfreemem(table);
261  PQfreemem(field);
262  }
263  PQclear(res);
264 
265  /*
266  * Now, those entries remaining in vacuum_l are orphans. Delete 'em.
267  *
268  * We don't want to run each delete as an individual transaction, because
269  * the commit overhead would be high. However, since 9.0 the backend will
270  * acquire a lock per deleted LO, so deleting too many LOs per transaction
271  * risks running out of room in the shared-memory lock table. Accordingly,
272  * we delete up to transaction_limit LOs per transaction.
273  */
274  res = PQexec(conn, "begin");
276  {
277  pg_log_error("failed to start transaction: %s", PQerrorMessage(conn));
278  PQclear(res);
279  PQfinish(conn);
280  return -1;
281  }
282  PQclear(res);
283 
284  buf[0] = '\0';
285  strcat(buf,
286  "DECLARE myportal CURSOR WITH HOLD FOR SELECT lo FROM vacuum_l");
287  res = PQexec(conn, buf);
289  {
290  pg_log_error("DECLARE CURSOR failed: %s", PQerrorMessage(conn));
291  PQclear(res);
292  PQfinish(conn);
293  return -1;
294  }
295  PQclear(res);
296 
297  snprintf(buf, BUFSIZE, "FETCH FORWARD %ld IN myportal",
298  param->transaction_limit > 0 ? param->transaction_limit : 1000L);
299 
300  deleted = 0;
301 
302  do
303  {
304  res = PQexec(conn, buf);
306  {
307  pg_log_error("FETCH FORWARD failed: %s", PQerrorMessage(conn));
308  PQclear(res);
309  PQfinish(conn);
310  return -1;
311  }
312 
313  matched = PQntuples(res);
314  if (matched <= 0)
315  {
316  /* at end of resultset */
317  PQclear(res);
318  break;
319  }
320 
321  for (i = 0; i < matched; i++)
322  {
323  Oid lo = atooid(PQgetvalue(res, i, 0));
324 
325  if (param->verbose)
326  {
327  fprintf(stdout, "\rRemoving lo %6u ", lo);
328  fflush(stdout);
329  }
330 
331  if (param->dry_run == 0)
332  {
333  if (lo_unlink(conn, lo) < 0)
334  {
335  pg_log_error("failed to remove lo %u: %s", lo,
338  {
339  success = false;
340  break; /* out of inner for-loop */
341  }
342  }
343  else
344  deleted++;
345  }
346  else
347  deleted++;
348 
349  if (param->transaction_limit > 0 &&
350  (deleted % param->transaction_limit) == 0)
351  {
352  res2 = PQexec(conn, "commit");
353  if (PQresultStatus(res2) != PGRES_COMMAND_OK)
354  {
355  pg_log_error("failed to commit transaction: %s",
357  PQclear(res2);
358  PQclear(res);
359  PQfinish(conn);
360  return -1;
361  }
362  PQclear(res2);
363  res2 = PQexec(conn, "begin");
364  if (PQresultStatus(res2) != PGRES_COMMAND_OK)
365  {
366  pg_log_error("failed to start transaction: %s",
368  PQclear(res2);
369  PQclear(res);
370  PQfinish(conn);
371  return -1;
372  }
373  PQclear(res2);
374  }
375  }
376 
377  PQclear(res);
378  } while (success);
379 
380  /*
381  * That's all folks!
382  */
383  res = PQexec(conn, "commit");
385  {
386  pg_log_error("failed to commit transaction: %s",
388  PQclear(res);
389  PQfinish(conn);
390  return -1;
391  }
392  PQclear(res);
393 
394  PQfinish(conn);
395 
396  if (param->verbose)
397  {
398  if (param->dry_run)
399  fprintf(stdout, "\rWould remove %ld large objects from database \"%s\".\n",
400  deleted, database);
401  else if (success)
402  fprintf(stdout,
403  "\rSuccessfully removed %ld large objects from database \"%s\".\n",
404  deleted, database);
405  else
406  fprintf(stdout, "\rRemoval from database \"%s\" failed at object %ld of %ld.\n",
407  database, deleted, matched);
408  }
409 
410  return ((param->dry_run || success) ? 0 : -1);
411 }
412 
413 static void
414 usage(const char *progname)
415 {
416  printf("%s removes unreferenced large objects from databases.\n\n", progname);
417  printf("Usage:\n %s [OPTION]... DBNAME...\n\n", progname);
418  printf("Options:\n");
419  printf(" -l, --limit=LIMIT commit after removing each LIMIT large objects\n");
420  printf(" -n, --dry-run don't remove large objects, just show what would be done\n");
421  printf(" -v, --verbose write a lot of progress messages\n");
422  printf(" -V, --version output version information, then exit\n");
423  printf(" -?, --help show this help, then exit\n");
424  printf("\nConnection options:\n");
425  printf(" -h, --host=HOSTNAME database server host or socket directory\n");
426  printf(" -p, --port=PORT database server port\n");
427  printf(" -U, --username=USERNAME user name to connect as\n");
428  printf(" -w, --no-password never prompt for password\n");
429  printf(" -W, --password force password prompt\n");
430  printf("\n");
431  printf("Report bugs to <%s>.\n", PACKAGE_BUGREPORT);
432  printf("%s home page: <%s>\n", PACKAGE_NAME, PACKAGE_URL);
433 }
434 
435 
436 int
437 main(int argc, char **argv)
438 {
439  static struct option long_options[] = {
440  {"host", required_argument, NULL, 'h'},
441  {"limit", required_argument, NULL, 'l'},
442  {"dry-run", no_argument, NULL, 'n'},
443  {"port", required_argument, NULL, 'p'},
444  {"username", required_argument, NULL, 'U'},
445  {"verbose", no_argument, NULL, 'v'},
446  {"version", no_argument, NULL, 'V'},
447  {"no-password", no_argument, NULL, 'w'},
448  {"password", no_argument, NULL, 'W'},
449  {"help", no_argument, NULL, '?'},
450  {NULL, 0, NULL, 0}
451  };
452 
453  int rc = 0;
454  struct _param param;
455  int c;
456  int port;
457  const char *progname;
458  int optindex;
459 
460  pg_logging_init(argv[0]);
461  progname = get_progname(argv[0]);
462 
463  /* Set default parameter values */
464  param.pg_user = NULL;
465  param.pg_prompt = TRI_DEFAULT;
466  param.pg_host = NULL;
467  param.pg_port = NULL;
468  param.progname = progname;
469  param.verbose = 0;
470  param.dry_run = 0;
471  param.transaction_limit = 1000;
472 
473  /* Process command-line arguments */
474  if (argc > 1)
475  {
476  if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
477  {
478  usage(progname);
479  exit(0);
480  }
481  if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
482  {
483  puts("vacuumlo (PostgreSQL) " PG_VERSION);
484  exit(0);
485  }
486  }
487 
488  while ((c = getopt_long(argc, argv, "h:l:np:U:vwW", long_options, &optindex)) != -1)
489  {
490  switch (c)
491  {
492  case 'h':
493  param.pg_host = pg_strdup(optarg);
494  break;
495  case 'l':
496  param.transaction_limit = strtol(optarg, NULL, 10);
497  if (param.transaction_limit < 0)
498  pg_fatal("transaction limit must not be negative (0 disables)");
499  break;
500  case 'n':
501  param.dry_run = 1;
502  param.verbose = 1;
503  break;
504  case 'p':
505  port = strtol(optarg, NULL, 10);
506  if ((port < 1) || (port > 65535))
507  pg_fatal("invalid port number: %s", optarg);
508  param.pg_port = pg_strdup(optarg);
509  break;
510  case 'U':
511  param.pg_user = pg_strdup(optarg);
512  break;
513  case 'v':
514  param.verbose = 1;
515  break;
516  case 'w':
517  param.pg_prompt = TRI_NO;
518  break;
519  case 'W':
520  param.pg_prompt = TRI_YES;
521  break;
522  default:
523  /* getopt_long already emitted a complaint */
524  pg_log_error_hint("Try \"%s --help\" for more information.", progname);
525  exit(1);
526  }
527  }
528 
529  /* No database given? Show usage */
530  if (optind >= argc)
531  {
532  pg_log_error("missing required argument: database name");
533  pg_log_error_hint("Try \"%s --help\" for more information.", progname);
534  exit(1);
535  }
536 
537  for (c = optind; c < argc; c++)
538  {
539  /* Work on selected database */
540  rc += (vacuumlo(argv[c], &param) != 0);
541  }
542 
543  return rc;
544 }
static Datum values[MAXATTR]
Definition: bootstrap.c:156
#define CppAsString2(x)
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int PQserverVersion(const PGconn *conn)
Definition: fe-connect.c:6733
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PGTransactionStatusType PQtransactionStatus(const PGconn *conn)
Definition: fe-connect.c:6698
int PQconnectionNeedsPassword(const PGconn *conn)
Definition: fe-connect.c:6794
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ExecStatusType PQresultStatus(const PGresult *res)
Definition: fe-exec.c:3240
int PQntuples(const PGresult *res)
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PGresult * PQexec(PGconn *conn, const char *query)
Definition: fe-exec.c:2225
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Definition: fe-exec.c:3705
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Definition: fe-lobj.c:589
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Definition: fe_memutils.c:85
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Definition: getopt_long.c:57
#define no_argument
Definition: getopt_long.h:24
#define required_argument
Definition: getopt_long.h:25
static bool success
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int i
Definition: isn.c:73
@ CONNECTION_BAD
Definition: libpq-fe.h:61
@ PGRES_COMMAND_OK
Definition: libpq-fe.h:97
@ PGRES_TUPLES_OK
Definition: libpq-fe.h:100
@ PQTRANS_INERROR
Definition: libpq-fe.h:121
static void const char fflush(stdout)
exit(1)
void pg_logging_init(const char *argv0)
Definition: logging.c:83
#define pg_log_error(...)
Definition: logging.h:106
#define pg_log_error_hint(...)
Definition: logging.h:112
const char * progname
Definition: main.c:45
#define pg_fatal(...)
PGDLLIMPORT int optind
Definition: getopt.c:50
PGDLLIMPORT char * optarg
Definition: getopt.c:52
static int port
Definition: pg_regress.c:90
static char * buf
Definition: pg_test_fsync.c:67
const char * get_progname(const char *argv0)
Definition: path.c:574
#define snprintf
Definition: port.h:238
#define fprintf
Definition: port.h:242
#define printf(...)
Definition: port.h:244
unsigned int Oid
Definition: postgres_ext.h:31
#define atooid(x)
Definition: postgres_ext.h:42
char * c
char * simple_prompt(const char *prompt, bool echo)
Definition: sprompt.c:38
static char * password
Definition: streamutil.c:53
PGconn * conn
Definition: streamutil.c:54
long transaction_limit
Definition: vacuumlo.c:50
enum trivalue pg_prompt
Definition: vacuumlo.c:44
char * pg_port
Definition: vacuumlo.c:45
int dry_run
Definition: vacuumlo.c:49
char * pg_user
Definition: vacuumlo.c:43
int verbose
Definition: vacuumlo.c:48
const char * progname
Definition: vacuumlo.c:47
char * pg_host
Definition: vacuumlo.c:46
static void usage(const char *progname)
Definition: vacuumlo.c:414
int main(int argc, char **argv)
Definition: vacuumlo.c:437
#define PARAMS_ARRAY_SIZE
static int vacuumlo(const char *database, const struct _param *param)
Definition: vacuumlo.c:62
trivalue
Definition: vacuumlo.c:35
@ TRI_YES
Definition: vacuumlo.c:38
@ TRI_DEFAULT
Definition: vacuumlo.c:36
@ TRI_NO
Definition: vacuumlo.c:37
#define BUFSIZE
Definition: vacuumlo.c:32