sqlite/test/attach2.test

# 2003 July 1
#
# 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.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script is testing the ATTACH and DETACH commands
# and related functionality.
#
# $Id: attach2.test,v 1.15 2004/06/09 21:01:12 drh Exp $
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl


# Ticket #354
#
# Databases test.db and test2.db contain identical schemas.  Make
# sure we can attach test2.db from test.db.
#
do_test attach2-1.1 {
  db eval {
    CREATE TABLE t1(a,b);
    CREATE INDEX x1 ON t1(a);
  }
  file delete -force test2.db
  file delete -force test2.db-journal
  sqlite db2 test2.db
  db2 eval {
    CREATE TABLE t1(a,b);
    CREATE INDEX x1 ON t1(a);
  }
  catchsql {
    ATTACH 'test2.db' AS t2;
  }
} {0 {}}

# Ticket #514
#
proc db_list {db} {
  set list {}
  foreach {idx name file} [execsql {PRAGMA database_list} $db] {
    lappend list $idx $name
  }
  return $list
}
db eval {DETACH t2}
do_test attach2-2.1 {
  # lock test2.db then try to attach it.  This is no longer an error because
  # db2 just RESERVES the database.  It does not obtain a write-lock until
  # we COMMIT.
  db2 eval {BEGIN}
  db2 eval {UPDATE t1 SET a = 0 WHERE 0}
  catchsql {
    ATTACH 'test2.db' AS t2;
  }
} {0 {}}
do_test attach2-2.2 {
  # make sure test2.db did get attached.
  db_list db
} {0 main 1 temp 2 t2}
db2 eval {COMMIT}

do_test attach2-2.5 {
  # Make sure we can read test2.db from db
  catchsql {
    SELECT name FROM t2.sqlite_master;
  }
} {0 {t1 x1}}
do_test attach2-2.6 {
  # lock test2.db and try to read from it.  This should still work because
  # the lock is only a RESERVED lock which does not prevent reading.
  #
  db2 eval BEGIN
  db2 eval {UPDATE t1 SET a = 0 WHERE 0}
  catchsql {
    SELECT name FROM t2.sqlite_master;
  }
} {0 {t1 x1}}
do_test attach2-2.7 {
  # but we can still read from test1.db even though test2.db is locked.
  catchsql {
    SELECT name FROM main.sqlite_master;
  }
} {0 {t1 x1}}
do_test attach2-2.8 {
  # start a transaction on test.db even though test2.db is locked.
  catchsql {
    BEGIN;
    INSERT INTO t1 VALUES(8,9);
  }
} {0 {}}
do_test attach2-2.9 {
  execsql {
    SELECT * FROM t1
  }
} {8 9}
do_test attach2-2.10 {
  # now try to write to test2.db.  the write should fail
  catchsql {
    INSERT INTO t2.t1 VALUES(1,2);
  }
} {1 {database is locked}}
do_test attach2-2.11 {
  # when the write failed in the previous test, the transaction should
  # have rolled back.
  # 
  # Update for version 3: A transaction is no longer rolled back if a
  #                       database is found to be busy.
  execsql {rollback}
  db2 eval ROLLBACK
  execsql {
    SELECT * FROM t1
  }
} {}
do_test attach2-2.12 {
  catchsql {
    COMMIT
  }
} {1 {cannot commit - no transaction is active}}

# Ticket #574:  Make sure it works using the non-callback API
#
do_test attach2-3.1 {
  db close
  set DB [sqlite db test.db]
  set rc [catch {sqlite3_prepare $DB "ATTACH 'test2.db' AS t2" -1 TAIL} VM]
  if {$rc} {lappend rc $VM}
  sqlite3_finalize $VM
  set rc
} {0}
do_test attach2-3.2 {
  set rc [catch {sqlite3_prepare $DB "DETACH t2" -1 TAIL} VM]
  if {$rc} {lappend rc $VM}
  sqlite3_finalize $VM
  set rc
} {0}

db close
for {set i 2} {$i<=15} {incr i} {
  catch {db$i close}
}

# A procedure to verify the status of locks on a database.
#
proc lock_status {testnum db expected_result} {
  do_test attach2-$testnum [subst {
    execsql {PRAGMA lock_status} $db
  }] $expected_result
}
set sqlite_os_trace 0

# Tests attach2-4.* test that read-locks work correctly with attached
# databases.
do_test attach2-4.1 {
  sqlite db test.db
  sqlite db2 test.db
  execsql {ATTACH 'test2.db' as file2}
  execsql {ATTACH 'test2.db' as file2} db2
} {}

lock_status 4.1.1 db {main unlocked temp unlocked file2 unlocked}
lock_status 4.1.2 db2 {main unlocked temp unlocked file2 unlocked}

do_test attach2-4.2 {
  # Handle 'db' read-locks test.db
  execsql {BEGIN}
  execsql {SELECT * FROM t1}
  # Lock status:
  #    db  - shared(main)
  #    db2 -
} {}

lock_status 4.2.1 db {main shared temp shared file2 unlocked}
lock_status 4.2.2 db2 {main unlocked temp unlocked file2 unlocked}

do_test attach2-4.3 {
  # The read lock held by db does not prevent db2 from reading test.db
  execsql {SELECT * FROM t1} db2
} {}

lock_status 4.3.1 db {main shared temp shared file2 unlocked}
lock_status 4.3.2 db2 {main unlocked temp unlocked file2 unlocked}

do_test attach2-4.4 {
  # db is holding a read lock on test.db, so we should not be able
  # to commit a write to test.db from db2
  catchsql {
    INSERT INTO t1 VALUES(1, 2)
  } db2 
} {1 {database is locked}}

lock_status 4.4.1 db {main shared temp shared file2 unlocked}
lock_status 4.4.2 db2 {main unlocked temp unlocked file2 unlocked}

do_test attach2-4.5 {
  # Handle 'db2' reserves file2.
  execsql {BEGIN} db2
  execsql {INSERT INTO file2.t1 VALUES(1, 2)} db2
  # Lock status:
  #    db  - shared(main)
  #    db2 - reserved(file2)
} {}

lock_status 4.5.1 db {main shared temp shared file2 unlocked}
lock_status 4.5.2 db2 {main unlocked temp reserved file2 reserved}

do_test attach2-4.6.1 {
  # Reads are allowed against a reserved database.
  catchsql {
    SELECT * FROM file2.t1;
  }
  # Lock status:
  #    db  - shared(main), shared(file2)
  #    db2 - reserved(file2)
} {0 {}}

lock_status 4.6.1.1 db {main shared temp shared file2 shared}
lock_status 4.6.1.2 db2 {main unlocked temp reserved file2 reserved}

do_test attach2-4.6.2 {
  # Writes against a reserved database are not allowed.
  catchsql {
    UPDATE file2.t1 SET a=0;
  }
} {1 {database is locked}}

lock_status 4.6.2.1 db {main shared temp reserved file2 shared}
lock_status 4.6.2.2 db2 {main unlocked temp reserved file2 reserved}

do_test attach2-4.7 {
  # Ensure handle 'db' retains the lock on the main file after
  # failing to obtain a write-lock on file2.
  catchsql {
    INSERT INTO t1 VALUES(1, 2)
  } db2 
} {0 {}}

lock_status 4.7.1 db {main shared temp reserved file2 shared}
lock_status 4.7.2 db2 {main reserved temp reserved file2 reserved}

do_test attach2-4.8 {
  # We should still be able to read test.db from db2
  execsql {SELECT * FROM t1} db2
} {1 2}

lock_status 4.8.1 db {main shared temp reserved file2 shared}
lock_status 4.8.2 db2 {main reserved temp reserved file2 reserved}

do_test attach2-4.9 {
  # Try to upgrade the handle 'db' lock.
  catchsql {
    INSERT INTO t1 VALUES(1, 2)
  }
} {1 {database is locked}}

lock_status 4.9.1 db {main shared temp reserved file2 shared}
lock_status 4.9.2 db2 {main reserved temp reserved file2 reserved}

set sqlite_os_trace 0
btree_breakpoint
do_test attach2-4.10 {
  # We cannot commit db2 while db is holding a read-lock
  catchsql {COMMIT} db2
} {1 {database is locked}}

lock_status 4.10.1 db {main shared temp reserved file2 shared}
lock_status 4.10.2 db2 {main reserved temp reserved file2 reserved}

do_test attach2-4.11 {
  # db is able to commit.
  catchsql {COMMIT}
} {0 {}}

lock_status 4.11.1 db {main unlocked temp unlocked file2 unlocked}
lock_status 4.11.2 db2 {main reserved temp reserved file2 reserved}

do_test attach2-4.12 {
  # Now we can commit db2
  catchsql {COMMIT} db2
} {0 {}}

lock_status 4.12.1 db {main unlocked temp unlocked file2 unlocked}
lock_status 4.12.2 db2 {main unlocked temp unlocked file2 unlocked}

do_test attach2-4.13 {
  execsql {SELECT * FROM file2.t1}
} {1 2}
do_test attach2-4.14 {
  execsql {INSERT INTO t1 VALUES(1, 2)}
} {}
do_test attach2-4.15 {
  execsql {SELECT * FROM t1} db2
} {1 2 1 2}

db close
db2 close
file delete -force test2.db

finish_test