# 2005 December 30 # # The author disclaims copyright to this source code. In place of # a legal notice, here is a blessing: # # May you do good and not evil. # May you find forgiveness for yourself and forgive others. # May you share freely, never taking more than you give. # #*********************************************************************** # # $Id: shared.test,v 1.8 2006/01/09 16:12:05 danielk1977 Exp $ set testdir [file dirname $argv0] source $testdir/tester.tcl db close ifcapable !shared_cache { finish_test return } set ::enable_shared_cache [sqlite3_enable_shared_cache 1] # Test organization: # # shared-1.*: Simple test to verify basic sanity of table level locking when # two connections share a pager cache. # shared-2.*: Test that a read transaction can co-exist with a # write-transaction, including a simple test to ensure the # external locking protocol is still working. # shared-3.*: Simple test of read-uncommitted mode. # shared-4.*: Check that the schema is locked and unlocked correctly. # shared-5.*: Test that creating/dropping schema items works when databases # are attached in different orders to different handles. # shared-6.*: Locking, UNION ALL queries and sub-queries. # shared-7.*: Autovacuum and shared-cache. # do_test shared-1.1 { # Open a second database on the file test.db. It should use the same pager # cache and schema as the original connection. Verify that only 1 file is # opened. sqlite3 db2 test.db sqlite3 db test.db set ::sqlite_open_file_count } {1} do_test shared-1.2 { # Add a table and a single row of data via the first connection. # Ensure that the second connection can see them. execsql { CREATE TABLE abc(a, b, c); INSERT INTO abc VALUES(1, 2, 3); } db execsql { SELECT * FROM abc; } db2 } {1 2 3} do_test shared-1.3 { # Have the first connection begin a transaction and obtain a read-lock # on table abc. This should not prevent the second connection from # querying abc. execsql { BEGIN; SELECT * FROM abc; } execsql { SELECT * FROM abc; } db2 } {1 2 3} do_test shared-1.4 { # Try to insert a row into abc via connection 2. This should fail because # of the read-lock connection 1 is holding on table abc (obtained in the # previous test case). catchsql { INSERT INTO abc VALUES(4, 5, 6); } db2 } {1 {database table is locked: abc}} do_test shared-1.5 { # Using connection 2 (the one without the open transaction), try to create # a new table. This should fail because of the open read transaction # held by connection 1. catchsql { CREATE TABLE def(d, e, f); } db2 } {1 {database table is locked: sqlite_master}} do_test shared-1.6 { # Upgrade connection 1's transaction to a write transaction. Create # a new table - def - and insert a row into it. Because the connection 1 # transaction modifies the schema, it should not be possible for # connection 2 to access the database at all until the connection 1 # has finished the transaction. execsql { CREATE TABLE def(d, e, f); INSERT INTO def VALUES('IV', 'V', 'VI'); } } {} do_test shared-1.7 { # Read from the sqlite_master table with connection 1 (inside the # transaction). Then test that we can not do this with connection 2. This # is because of the schema-modified lock established by connection 1 # in the previous test case. execsql { SELECT * FROM sqlite_master; } catchsql { SELECT * FROM sqlite_master; } db2 } {1 {database schema is locked: main}} do_test shared-1.8 { # Commit the connection 1 transaction. execsql { COMMIT; } } {} do_test shared-2.1 { # Open connection db3 to the database. Use a different path to the same # file so that db3 does *not* share the same pager cache as db and db2 # (there should be two open file handles). sqlite3 db3 ./test.db set ::sqlite_open_file_count } {2} do_test shared-2.2 { # Start read transactions on db and db2 (the shared pager cache). Ensure # db3 cannot write to the database. execsql { BEGIN; SELECT * FROM abc; } execsql { BEGIN; SELECT * FROM abc; } db2 catchsql { INSERT INTO abc VALUES(1, 2, 3); } db2 } {1 {database table is locked: abc}} do_test shared-2.3 { # Turn db's transaction into a write-transaction. db3 should still be # able to read from table def (but will not see the new row). Connection # db2 should not be able to read def (because of the write-lock). # Todo: The failed "INSERT INTO abc ..." statement in the above test # has started a write-transaction on db2 (should this be so?). This # would prevent connection db from starting a write-transaction. So roll the # db2 transaction back and replace it with a new read transaction. execsql { ROLLBACK; BEGIN; SELECT * FROM abc; } db2 execsql { INSERT INTO def VALUES('VII', 'VIII', 'IX'); } concat [ catchsql { SELECT * FROM def; } db3 ] [ catchsql { SELECT * FROM def; } db2 ] } {0 {IV V VI} 1 {database table is locked: def}} do_test shared-2.4 { # Commit the open transaction on db. db2 still holds a read-transaction. # This should prevent db3 from writing to the database, but not from # reading. execsql { COMMIT; } concat [ catchsql { SELECT * FROM def; } db3 ] [ catchsql { INSERT INTO def VALUES('X', 'XI', 'XII'); } db3 ] } {0 {IV V VI VII VIII IX} 1 {database is locked}} catchsql COMMIT db2 do_test shared-3.1.1 { # This test case starts a linear scan of table 'seq' using a # read-uncommitted connection. In the middle of the scan, rows are added # to the end of the seq table (ahead of the current cursor position). # The uncommitted rows should be included in the results of the scan. execsql " CREATE TABLE seq(i, x); INSERT INTO seq VALUES(1, '[string repeat X 500]'); INSERT INTO seq VALUES(2, '[string repeat X 500]'); " execsql {SELECT * FROM sqlite_master} db2 execsql {PRAGMA read_uncommitted = 1} db2 set ret [list] db2 eval {SELECT i FROM seq} { if {$i < 4} { execsql { INSERT INTO seq SELECT i + (SELECT max(i) FROM seq), x FROM seq; } } lappend ret $i } set ret } {1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16} do_test shared-3.1.2 { # Another linear scan through table seq using a read-uncommitted connection. # This time, delete each row as it is read. Should not affect the results of # the scan, but the table should be empty after the scan is concluded # (test 3.1.3 verifies this). set ret [list] db2 eval {SELECT i FROM seq} { db eval {DELETE FROM seq WHERE i = $i} lappend ret $i } set ret } {1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16} do_test shared-3.1.3 { execsql { SELECT * FROM seq; } } {} catch {db close} catch {db2 close} catch {db3 close} #-------------------------------------------------------------------------- # Tests shared-4.* test that the schema locking rules are applied # correctly. i.e.: # # 1. All transactions require a read-lock on the schemas of databases they # access. # 2. Transactions that modify a database schema require a write-lock on that # schema. # 3. It is not possible to compile a statement while another handle has a # write-lock on the schema. # # Open two database handles db and db2. Each has a single attach database # (as well as main): # # db.main -> ./test.db # db.test2 -> ./test2.db # db2.main -> ./test2.db # db2.test -> ./test.db # file delete -force test.db file delete -force test2.db file delete -force test2.db-journal sqlite3 db test.db sqlite3 db2 test2.db do_test shared-4.1.1 { set sqlite_open_file_count } {2} do_test shared-4.1.2 { execsql {ATTACH 'test2.db' AS test2} set sqlite_open_file_count } {2} do_test shared-4.1.3 { execsql {ATTACH 'test.db' AS test} db2 set sqlite_open_file_count } {2} # Sanity check: Create a table in ./test.db via handle db, and test that handle # db2 can "see" the new table immediately. A handle using a seperate pager # cache would have to reload the database schema before this were possible. # do_test shared-4.2.1 { execsql { CREATE TABLE abc(a, b, c); CREATE TABLE def(d, e, f); INSERT INTO abc VALUES('i', 'ii', 'iii'); INSERT INTO def VALUES('I', 'II', 'III'); } } {} do_test shared-4.2.2 { execsql { SELECT * FROM test.abc; } db2 } {i ii iii} # Open a read-transaction and read from table abc via handle 2. Check that # handle 1 can read table abc. Check that handle 1 cannot modify table abc # or the database schema. Then check that handle 1 can modify table def. # do_test shared-4.3.1 { execsql { BEGIN; SELECT * FROM test.abc; } db2 } {i ii iii} do_test shared-4.3.2 { catchsql { INSERT INTO abc VALUES('iv', 'v', 'vi'); } } {1 {database table is locked: abc}} do_test shared-4.3.3 { catchsql { CREATE TABLE ghi(g, h, i); } } {1 {database table is locked: sqlite_master}} do_test shared-4.3.3 { catchsql { INSERT INTO def VALUES('IV', 'V', 'VI'); } } {0 {}} do_test shared-4.3.4 { # Cleanup: commit the transaction opened by db2. execsql { COMMIT } db2 } {} # Open a write-transaction using handle 1 and modify the database schema. # Then try to execute a compiled statement to read from the same # database via handle 2 (fails to get the lock on sqlite_master). Also # try to compile a read of the same database using handle 2 (also fails). # Finally, compile a read of the other database using handle 2. This # should also fail. # do_test shared-4.4.1.2 { # Sanity check 1: Check that the schema is what we think it is when viewed # via handle 1. execsql { CREATE TABLE test2.ghi(g, h, i); SELECT 'test.db:'||name FROM sqlite_master UNION ALL SELECT 'test2.db:'||name FROM test2.sqlite_master; } } {test.db:abc test.db:def test2.db:ghi} do_test shared-4.4.1.2 { # Sanity check 2: Check that the schema is what we think it is when viewed # via handle 2. execsql { SELECT 'test2.db:'||name FROM sqlite_master UNION ALL SELECT 'test.db:'||name FROM test.sqlite_master; } db2 } {test2.db:ghi test.db:abc test.db:def} do_test shared-4.4.2 { set ::DB2 [sqlite3_connection_pointer db2] set sql {SELECT * FROM abc} set ::STMT1 [sqlite3_prepare $::DB2 $sql -1 DUMMY] execsql { BEGIN; CREATE TABLE jkl(j, k, l); } sqlite3_step $::STMT1 } {SQLITE_ERROR} do_test shared-4.4.3 { sqlite3_finalize $::STMT1 } {SQLITE_LOCKED} do_test shared-4.4.4 { set rc [catch { set ::STMT1 [sqlite3_prepare $::DB2 $sql -1 DUMMY] } msg] list $rc $msg } {1 {(6) database schema is locked: test}} do_test shared-4.4.5 { set rc [catch { set ::STMT1 [sqlite3_prepare $::DB2 "SELECT * FROM ghi" -1 DUMMY] } msg] list $rc $msg } {1 {(6) database schema is locked: test}} catch {db2 close} catch {db close} #-------------------------------------------------------------------------- # Tests shared-5.* # foreach db [list test.db test1.db test2.db test3.db] { file delete -force $db ${db}-journal } do_test shared-5.1.1 { sqlite3 db1 test.db sqlite3 db2 test.db execsql { ATTACH 'test1.db' AS test1; ATTACH 'test2.db' AS test2; ATTACH 'test3.db' AS test3; } db1 execsql { ATTACH 'test3.db' AS test3; ATTACH 'test2.db' AS test2; ATTACH 'test1.db' AS test1; } db2 } {} do_test shared-5.1.2 { execsql { CREATE TABLE test1.t1(a, b); CREATE INDEX test1.i1 ON t1(a, b); CREATE VIEW test1.v1 AS SELECT * FROM t1; CREATE TRIGGER test1.trig1 AFTER INSERT ON t1 BEGIN INSERT INTO t1 VALUES(new.a, new.b); END; } db1 execsql { DROP INDEX i1; DROP VIEW v1; DROP TRIGGER trig1; DROP TABLE t1; } db2 } {} do_test shared-5.1.2 { execsql { SELECT * FROM sqlite_master UNION ALL SELECT * FROM test1.sqlite_master } db1 } {} #-------------------------------------------------------------------------- # Tests shared-6.* test that a query obtains all the read-locks it needs # before starting execution of the query. This means that there is no chance # some rows of data will be returned before a lock fails and SQLITE_LOCK # is returned. # do_test shared-6.1.1 { execsql { CREATE TABLE t1(a, b); CREATE TABLE t2(a, b); INSERT INTO t1 VALUES(1, 2); INSERT INTO t2 VALUES(3, 4); } db1 execsql { SELECT * FROM t1 UNION ALL SELECT * FROM t2; } db2 } {1 2 3 4} do_test shared-6.1.2 { # Establish a write lock on table t2 via connection db2. Then make a # UNION all query using connection db1 that first accesses t1, followed # by t2. If the locks are grabbed at the start of the statement (as # they should be), no rows are returned. If (as was previously the case) # they are grabbed as the tables are accessed, the t1 rows will be # returned before the query fails. # execsql { BEGIN; INSERT INTO t2 VALUES(5, 6); } db2 set ret [list] catch { db1 eval {SELECT * FROM t1 UNION ALL SELECT * FROM t2} { lappend ret $a $b } } set ret } {} do_test shared-6.1.3 { execsql { COMMIT; BEGIN; INSERT INTO t1 VALUES(7, 8); } db2 set ret [list] catch { db1 eval { SELECT (CASE WHEN a>4 THEN (SELECT a FROM t1) ELSE 0 END) AS d FROM t2; } { lappend ret $d } } set ret } {} catch {db1 close} catch {db2 close} foreach f [list test.db test2.db] { file delete -force $f ${f}-journal } #-------------------------------------------------------------------------- # Tests shared-7.* test auto-vacuum does not invalidate cursors from # other shared-cache users when it reorganizes the database on # COMMIT. # do_test shared-7.1 { # This test case sets up a test database in auto-vacuum mode consisting # of two tables, t1 and t2. Both have a single index. Table t1 is # populated first (so consists of pages toward the start of the db file), # t2 second (pages toward the end of the file). sqlite3 db test.db sqlite3 db2 test.db execsql { PRAGMA auto_vacuum = 1; BEGIN; CREATE TABLE t1(a PRIMARY KEY, b); CREATE TABLE t2(a PRIMARY KEY, b); } for {set i 0} {$i < 100} {incr i} { set a [string repeat "$i " 20] set b [string repeat "$i " 20] db eval { INSERT INTO t1 VALUES($a, $b); } lappend ::contents [list [expr $i+1] $a $b] } execsql { INSERT INTO t2 SELECT * FROM t1; COMMIT; } execsql { PRAGMA auto_vacuum; } } {1} do_test shared-7.2 { # This test case deletes the contents of table t1 (the one at the start of # the file) while many cursors are open on table t2 and it's index. All of # the non-root pages will be moved from the end to the start of the file # when the DELETE is committed - this test verifies that moving the pages # does not disturb the open cursors. # proc lockrow {db tbl oids body} { set ret [list] db eval "SELECT oid AS i, a, b FROM $tbl ORDER BY a" { if {$i==[lindex $oids 0]} { set noids [lrange $oids 1 end] if {[llength $noids]==0} { set subret [eval $body] } else { set subret [lockrow $db $tbl $noids $body] } } lappend ret [list $i $a $b] } return [linsert $subret 0 $ret] } proc locktblrows {db tbl body} { set oids [db eval "SELECT oid FROM $tbl"] lockrow $db $tbl $oids $body } set scans [locktblrows db t2 { execsql { DELETE FROM t1; } db2 }] set error 0 # Test that each SELECT query returned the expected contents of t2. foreach s $scans { if {[lsort -integer -index 0 $s]!=$::contents} { set error 1 } } set error } {0} catch {db close} catch {db2 close} #-------------------------------------------------------------------------- # The following tests try to trick the shared-cache code into assuming # the wrong encoding for a database. # file delete -force test.db test.db-journal do_test shared-8.1.1 { sqlite3 db test.db execsql { PRAGMA encoding = 'UTF-16'; SELECT * FROM sqlite_master; } } {} do_test shared-8.1.2 { string range [execsql {PRAGMA encoding;}] 0 end-2 } {UTF-16} do_test shared-8.1.3 { sqlite3 db2 test.db execsql { PRAGMA encoding = 'UTF-8'; CREATE TABLE abc(a, b, c); } db2 } {} do_test shared-8.1.4 { execsql { SELECT * FROM sqlite_master; } } "table abc abc [expr $AUTOVACUUM?3:2] {CREATE TABLE abc(a, b, c)}" do_test shared-8.1.5 { db2 close execsql { PRAGMA encoding; } } {UTF-8} file delete -force test2.db test2.db-journal do_test shared-8.2.1 { execsql { ATTACH 'test2.db' AS aux; SELECT * FROM aux.sqlite_master; } } {} do_test shared-8.2.2 { sqlite3 db2 test2.db execsql { PRAGMA encoding = 'UTF-16'; CREATE TABLE def(d, e, f); } db2 string range [execsql {PRAGMA encoding;} db2] 0 end-2 } {UTF-16} do_test shared-8.2.3 { catchsql { SELECT * FROM aux.sqlite_master; } } {1 {attached databases must use the same text encoding as main database}} catch {db close} catch {db2 close} finish_test sqlite3_enable_shared_cache $::enable_shared_cache