xref: /sqlite-3.40.0/test/e_vacuum.test (revision fcd71b60)
1# 2010 September 24
2#
3# The author disclaims copyright to this source code.  In place of
4# a legal notice, here is a blessing:
5#
6#    May you do good and not evil.
7#    May you find forgiveness for yourself and forgive others.
8#    May you share freely, never taking more than you give.
9#
10#***********************************************************************
11#
12# This file implements tests to verify that the "testable statements" in
13# the lang_vacuum.html document are correct.
14#
15
16set testdir [file dirname $argv0]
17source $testdir/tester.tcl
18
19sqlite3_test_control_pending_byte 0x1000000
20
21proc create_db {{sql ""}} {
22  catch { db close }
23  forcedelete test.db
24  sqlite3 db test.db
25
26  db transaction {
27    execsql { PRAGMA page_size = 1024; }
28    execsql $sql
29    execsql {
30      CREATE TABLE t1(a PRIMARY KEY, b UNIQUE);
31      INSERT INTO t1 VALUES(1, randomblob(400));
32      INSERT INTO t1 SELECT a+1,  randomblob(400) FROM t1;
33      INSERT INTO t1 SELECT a+2,  randomblob(400) FROM t1;
34      INSERT INTO t1 SELECT a+4,  randomblob(400) FROM t1;
35      INSERT INTO t1 SELECT a+8,  randomblob(400) FROM t1;
36      INSERT INTO t1 SELECT a+16, randomblob(400) FROM t1;
37      INSERT INTO t1 SELECT a+32, randomblob(400) FROM t1;
38      INSERT INTO t1 SELECT a+64, randomblob(400) FROM t1;
39
40      CREATE TABLE t2(a PRIMARY KEY, b UNIQUE);
41      INSERT INTO t2 SELECT * FROM t1;
42    }
43  }
44
45  return [expr {[file size test.db] / 1024}]
46}
47
48# This proc returns the number of contiguous blocks of pages that make up
49# the table or index named by the only argument. For example, if the table
50# occupies database pages 3, 4, 8 and 9, then this command returns 2 (there
51# are 2 fragments - one consisting of pages 3 and 4, the other of fragments
52# 8 and 9).
53#
54proc fragment_count {name} {
55  execsql { CREATE VIRTUAL TABLE temp.stat USING dbstat }
56  set nFrag 1
57  db eval {SELECT pageno FROM stat WHERE name = 't1' ORDER BY pageno} {
58    if {[info exists prevpageno] && $prevpageno != $pageno-1} {
59      incr nFrag
60    }
61    set prevpageno $pageno
62  }
63  execsql { DROP TABLE temp.stat }
64  set nFrag
65}
66
67
68# EVIDENCE-OF: R-63707-33375 -- syntax diagram vacuum-stmt
69#
70do_execsql_test e_vacuum-0.1 { VACUUM } {}
71
72# EVIDENCE-OF: R-51469-36013 Unless SQLite is running in
73# "auto_vacuum=FULL" mode, when a large amount of data is deleted from
74# the database file it leaves behind empty space, or "free" database
75# pages.
76#
77# EVIDENCE-OF: R-60541-63059 Running VACUUM to rebuild the database
78# reclaims this space and reduces the size of the database file.
79#
80foreach {tn avmode sz} {
81  1 none        7
82  2 full        8
83  3 incremental 8
84} {
85  set nPage [create_db "PRAGMA auto_vacuum = $avmode"]
86
87  do_execsql_test e_vacuum-1.1.$tn.1 {
88    DELETE FROM t1;
89    DELETE FROM t2;
90  } {}
91
92  if {$avmode == "full"} {
93    # This branch tests the "unless ... auto_vacuum=FULL" in the requirement
94    # above. If auto_vacuum is set to FULL, then no empty space is left in
95    # the database file.
96    do_execsql_test e_vacuum-1.1.$tn.2 {PRAGMA freelist_count} 0
97  } else {
98    set freelist [expr {$nPage - $sz}]
99    if {$avmode == "incremental"} {
100      # The page size is 1024 bytes. Therefore, assuming the database contains
101      # somewhere between 207 and 411 pages (it does), there are 2 pointer-map
102      # pages.
103      incr freelist -2
104    }
105    do_execsql_test e_vacuum-1.1.$tn.3 {PRAGMA freelist_count} $freelist
106    do_execsql_test e_vacuum-1.1.$tn.4 {VACUUM} {}
107  }
108
109  do_test e_vacuum-1.1.$tn.5 { expr {[file size test.db] / 1024} } $sz
110}
111
112# EVIDENCE-OF: R-50943-18433 Frequent inserts, updates, and deletes can
113# cause the database file to become fragmented - where data for a single
114# table or index is scattered around the database file.
115#
116# EVIDENCE-OF: R-05791-54928 Running VACUUM ensures that each table and
117# index is largely stored contiguously within the database file.
118#
119#   e_vacuum-1.2.1 - Perform many INSERT, UPDATE and DELETE ops on table t1.
120#   e_vacuum-1.2.2 - Verify that t1 and its indexes are now quite fragmented.
121#   e_vacuum-1.2.3 - Run VACUUM.
122#   e_vacuum-1.2.4 - Verify that t1 and its indexes are now much
123#                    less fragmented.
124#
125ifcapable vtab {
126  create_db
127  register_dbstat_vtab db
128  do_execsql_test e_vacuum-1.2.1 {
129    DELETE FROM t1 WHERE a%2;
130    INSERT INTO t1 SELECT b, a FROM t2 WHERE a%2;
131    UPDATE t1 SET b=randomblob(600) WHERE (a%2)==0;
132  } {}
133
134  do_test e_vacuum-1.2.2.1 { expr [fragment_count t1]>100 } 1
135  do_test e_vacuum-1.2.2.2 { expr [fragment_count sqlite_autoindex_t1_1]>100 } 1
136  do_test e_vacuum-1.2.2.3 { expr [fragment_count sqlite_autoindex_t1_2]>100 } 1
137
138  do_execsql_test e_vacuum-1.2.3 { VACUUM } {}
139
140  # In practice, the tables and indexes each end up stored as two fragments -
141  # one containing the root page and another containing all other pages.
142  #
143  do_test e_vacuum-1.2.4.1 { fragment_count t1 }                    2
144  do_test e_vacuum-1.2.4.2 { fragment_count sqlite_autoindex_t1_1 } 2
145  do_test e_vacuum-1.2.4.3 { fragment_count sqlite_autoindex_t1_2 } 2
146}
147
148# EVIDENCE-OF: R-20474-44465 Normally, the database page_size and
149# whether or not the database supports auto_vacuum must be configured
150# before the database file is actually created.
151#
152do_test e_vacuum-1.3.1.1 {
153  create_db "PRAGMA page_size = 1024 ; PRAGMA auto_vacuum = FULL"
154  execsql { PRAGMA page_size ; PRAGMA auto_vacuum }
155} {1024 1}
156do_test e_vacuum-1.3.1.2 {
157  execsql { PRAGMA page_size = 2048 }
158  execsql { PRAGMA auto_vacuum = NONE }
159  execsql { PRAGMA page_size ; PRAGMA auto_vacuum }
160} {1024 1}
161
162# EVIDENCE-OF: R-08570-19916 However, when not in write-ahead log mode,
163# the page_size and/or auto_vacuum properties of an existing database
164# may be changed by using the page_size and/or pragma auto_vacuum
165# pragmas and then immediately VACUUMing the database.
166#
167do_test e_vacuum-1.3.2.1 {
168  execsql { PRAGMA journal_mode = delete }
169  execsql { PRAGMA page_size = 2048 }
170  execsql { PRAGMA auto_vacuum = NONE }
171  execsql VACUUM
172  execsql { PRAGMA page_size ; PRAGMA auto_vacuum }
173} {2048 0}
174
175# EVIDENCE-OF: R-48521-51450 When in write-ahead log mode, only the
176# auto_vacuum support property can be changed using VACUUM.
177#
178ifcapable wal {
179do_test e_vacuum-1.3.3.1 {
180  execsql { PRAGMA journal_mode = wal }
181  execsql { PRAGMA page_size ; PRAGMA auto_vacuum }
182} {2048 0}
183do_test e_vacuum-1.3.3.2 {
184  execsql { PRAGMA page_size = 1024 }
185  execsql { PRAGMA auto_vacuum = FULL }
186  execsql VACUUM
187  execsql { PRAGMA page_size ; PRAGMA auto_vacuum }
188} {2048 1}
189}
190
191# EVIDENCE-OF: R-38001-03952 VACUUM only works on the main database. It
192# is not possible to VACUUM an attached database file.
193forcedelete test.db2
194create_db { PRAGMA auto_vacuum = NONE }
195do_execsql_test e_vacuum-2.1.1 {
196  ATTACH 'test.db2' AS aux;
197  PRAGMA aux.page_size = 1024;
198  CREATE TABLE aux.t3 AS SELECT * FROM t1;
199  DELETE FROM t3;
200} {}
201set original_size [file size test.db2]
202
203# Try everything we can think of to get the aux database vacuumed:
204do_execsql_test e_vacuum-2.1.3 { VACUUM } {}
205do_execsql_test e_vacuum-2.1.4 { VACUUM aux } {}
206do_execsql_test e_vacuum-2.1.5 { VACUUM 'test.db2' } {}
207
208# Despite our efforts, space in the aux database has not been reclaimed:
209do_test e_vacuum-2.1.6 { expr {[file size test.db2]==$::original_size} } 1
210
211# EVIDENCE-OF: R-17495-17419 The VACUUM command may change the ROWIDs of
212# entries in any tables that do not have an explicit INTEGER PRIMARY
213# KEY.
214#
215#   Tests e_vacuum-3.1.1 - 3.1.2 demonstrate that rowids can change when
216#   a database is VACUUMed. Tests e_vacuum-3.1.3 - 3.1.4 show that adding
217#   an INTEGER PRIMARY KEY column to a table stops this from happening.
218#
219do_execsql_test e_vacuum-3.1.1 {
220  CREATE TABLE t4(x);
221  INSERT INTO t4(x) VALUES('x');
222  INSERT INTO t4(x) VALUES('y');
223  INSERT INTO t4(x) VALUES('z');
224  DELETE FROM t4 WHERE x = 'y';
225  SELECT rowid, x FROM t4;
226} {1 x 3 z}
227do_execsql_test e_vacuum-3.1.2 {
228  VACUUM;
229  SELECT rowid, x FROM t4;
230} {1 x 2 z}
231
232do_execsql_test e_vacuum-3.1.3 {
233  CREATE TABLE t5(x, y INTEGER PRIMARY KEY);
234  INSERT INTO t5(x) VALUES('x');
235  INSERT INTO t5(x) VALUES('y');
236  INSERT INTO t5(x) VALUES('z');
237  DELETE FROM t5 WHERE x = 'y';
238  SELECT rowid, x FROM t5;
239} {1 x 3 z}
240do_execsql_test e_vacuum-3.1.4 {
241  VACUUM;
242  SELECT rowid, x FROM t5;
243} {1 x 3 z}
244
245# EVIDENCE-OF: R-49563-33883 A VACUUM will fail if there is an open
246# transaction, or if there are one or more active SQL statements when it
247# is run.
248#
249do_execsql_test  e_vacuum-3.2.1.1 { BEGIN } {}
250do_catchsql_test e_vacuum-3.2.1.2 {
251  VACUUM
252} {1 {cannot VACUUM from within a transaction}}
253do_execsql_test  e_vacuum-3.2.1.3 { COMMIT } {}
254do_execsql_test  e_vacuum-3.2.1.4 { VACUUM } {}
255do_execsql_test  e_vacuum-3.2.1.5 { SAVEPOINT x } {}
256do_catchsql_test e_vacuum-3.2.1.6 {
257  VACUUM
258} {1 {cannot VACUUM from within a transaction}}
259do_execsql_test  e_vacuum-3.2.1.7 { COMMIT } {}
260do_execsql_test  e_vacuum-3.2.1.8 { VACUUM } {}
261
262create_db
263do_test e_vacuum-3.2.2.1 {
264  set res ""
265  db eval { SELECT a FROM t1 } {
266    if {$a == 10} { set res [catchsql VACUUM] }
267  }
268  set res
269} {1 {cannot VACUUM - SQL statements in progress}}
270
271
272# EVIDENCE-OF: R-38735-12540 As of SQLite version 3.1, an alternative to
273# using the VACUUM command to reclaim space after data has been deleted
274# is auto-vacuum mode, enabled using the auto_vacuum pragma.
275#
276do_test e_vacuum-3.3.1 {
277  create_db { PRAGMA auto_vacuum = FULL }
278  execsql { PRAGMA auto_vacuum }
279} {1}
280
281# EVIDENCE-OF: R-64844-34873 When auto_vacuum is enabled for a database
282# free pages may be reclaimed after deleting data, causing the file to
283# shrink, without rebuilding the entire database using VACUUM.
284#
285do_test e_vacuum-3.3.2.1 {
286  create_db { PRAGMA auto_vacuum = FULL }
287  execsql {
288    DELETE FROM t1;
289    DELETE FROM t2;
290  }
291  expr {[file size test.db] / 1024}
292} {8}
293do_test e_vacuum-3.3.2.2 {
294  create_db { PRAGMA auto_vacuum = INCREMENTAL }
295  execsql {
296    DELETE FROM t1;
297    DELETE FROM t2;
298    PRAGMA incremental_vacuum;
299  }
300  expr {[file size test.db] / 1024}
301} {8}
302
303finish_test
304