Improvements to the way that truncation is implemented in sqlite_dbpage().

FossilOrigin-Name: ac4bb2e4ecf0bdb0d8ac12b1ccb42d51af02f519a038cfc79faab5c216971056

2 files changed, 118 insertions, 0 deletions

diff --git a/test/dbpage.test b/test/dbpage.test
index 0646a70b0..2c0725307 100644
--- a/test/dbpage.test
+++ b/test/dbpage.test
@@ -108,4 +108,96 @@ do_execsql_test 300 {
   SELECT * FROM sqlite_temp_schema, sqlite_dbpage;
 } {}
 
+#-------------------------------------------------------------------------
+reset_db
+do_execsql_test 400 {
+  ATTACH ':memory:' AS aux1;
+  BEGIN;
+    CREATE VIRTUAL TABLE aux1.t1 USING sqlite_dbpage;
+    INSERT INTO t1 VALUES(17, NULL);
+  COMMIT;
+}
+
+#-------------------------------------------------------------------------
+reset_db
+forcedelete test.db2
+sqlite3 db2 test.db2
+db2 eval {
+  CREATE TABLE t1(x, y);
+}
+
+do_execsql_test 500 {
+  CREATE TABLE x1(a);
+  INSERT INTO x1 VALUES( hex(randomblob(2000)) );
+  INSERT INTO x1 VALUES( hex(randomblob(2000)) );
+  INSERT INTO x1 VALUES( hex(randomblob(2000)) );
+  INSERT INTO x1 VALUES( hex(randomblob(2000)) );
+  PRAGMA page_count;
+} {18}
+
+do_test 510 {
+  db eval  BEGIN 
+  db2 eval { PRAGMA page_count } {
+    db eval {
+      INSERT INTO sqlite_dbpage values($page_count, NULL);
+    }
+  }
+  db2 eval { SELECT pgno, data FROM sqlite_dbpage } {
+    db eval {
+      INSERT INTO sqlite_dbpage values($pgno, $data);
+    }
+  }
+
+  db eval COMMIT
+} {}
+
+db close
+sqlite3 db test.db
+
+do_execsql_test 520 {
+  PRAGMA page_count;
+  SELECT * FROM t1;
+} {2}
+
+#-------------------------------------------------------------------------
+reset_db
+forcedelete test.db2
+do_execsql_test 610 {
+  ATTACH 'test.db2' AS aux;
+  CREATE TABLE t1(x);
+  CREATE TABLE t2(y);
+  INSERT INTO t1 VALUES(1234);
+  CREATE TABLE aux.x1(z);
+}
+
+set pgno [db one {SELECT max(rootpage) FROM sqlite_schema}]
+sqlite3 db2 test.db2
+db2 eval {
+  BEGIN;
+    SELECT * FROM x1;
+}
+
+do_catchsql_test 620 {
+  UPDATE sqlite_dbpage SET data = (
+    SELECT data FROM sqlite_dbpage WHERE pgno=$pgno-1
+  ) WHERE pgno = $pgno;
+} {1 {database is locked}}
+
+db2 eval {
+  COMMIT;
+}
+
+do_catchsql_test 630 {
+  UPDATE sqlite_dbpage SET data = (
+    SELECT data FROM sqlite_dbpage WHERE pgno=$pgno-1
+  ) WHERE pgno = $pgno;
+} {0 {}}
+
+db close
+sqlite3 db test.db
+
+do_execsql_test 640 {
+  SELECT * FROM t2;
+} {1234}
+
 finish_test
diff --git a/test/dbpagefault.test b/test/dbpagefault.test
index f27741cba..e5b246fc9 100644
--- a/test/dbpagefault.test
+++ b/test/dbpagefault.test
@@ -82,5 +82,31 @@ do_catchsql_test 3.2 {
 #  faultsim_test_result {0 {}}
 #}
 
+reset_db
+forcedelete test.db2
+do_execsql_test 4.0 {
+  CREATE TABLE t1(x);
+  INSERT INTO t1 VALUES('one');
+  CREATE TABLE t2(x);
+  INSERT INTO t2 VALUES('two');
+  ATTACH 'test.db2' AS aux;
+  CREATE TABLE aux.x1(x);
+}
+
+set pgno [db one {SELECT max(rootpage) FROM sqlite_schema}]
+
+faultsim_save_and_close
+do_faultsim_test 4 -prep {
+  faultsim_restore_and_reopen
+  execsql { ATTACH 'test.db2' AS aux; }
+} -body {
+  execsql { 
+    UPDATE sqlite_dbpage SET data = (
+      SELECT data FROM sqlite_dbpage WHERE pgno=($pgno-1)
+    ) WHERE pgno = $pgno;
+  }
+} -test {
+  faultsim_test_result {0 {}} {1 {unable to open a temporary database file for storing temporary tables}}
+}
 
 finish_test