It is now allowed to truncate a table if referential integrity has been disabled…

It is now allowed to truncate a table if referential integrity has been disabled for this table or database.

h2/src/main/org/h2/table/RegularTable.java

@@ -649,15 +649,17 @@ public class RegularTable extends TableBase {
     }
 
     public boolean canTruncate() {
-        ArrayList<Constraint> constraints = getConstraints();
-        for (int i = 0; constraints != null && i < constraints.size(); i++) {
-            Constraint c = constraints.get(i);
-            if (!(c.getConstraintType().equals(Constraint.REFERENTIAL))) {
-                continue;
-            }
-            ConstraintReferential ref = (ConstraintReferential) c;
-            if (ref.getRefTable() == this) {
-                return false;
+        if (getCheckForeignKeyConstraints() && database.getReferentialIntegrity()) {
+            ArrayList<Constraint> constraints = getConstraints();
+            for (int i = 0; constraints != null && i < constraints.size(); i++) {
+                Constraint c = constraints.get(i);
+                if (!(c.getConstraintType().equals(Constraint.REFERENTIAL))) {
+                    continue;
+                }
+                ConstraintReferential ref = (ConstraintReferential) c;
+                if (ref.getRefTable() == this) {
+                    return false;
+                }
             }
         }
         return true;

h2/src/test/org/h2/test/db/TestCases.java

@@ -36,6 +36,7 @@ public class TestCases extends TestBase {
     }
 
     public void test() throws Exception {
+        testTruncateConstraintsDisabled();
         testPreparedSubquery2();
         testPreparedSubquery();
         testCompareDoubleWithIntColumn();
@@ -81,6 +82,39 @@ public class TestCases extends TestBase {
         deleteDb("cases");
     }
 
+    private void testTruncateConstraintsDisabled() throws SQLException {
+        deleteDb("cases");
+        Connection conn = getConnection("cases");
+        Statement stat = conn.createStatement();
+        stat.execute("create table parent(id identity) as select 0");
+        stat.execute("create table child(id identity, parent int references parent(id)) as select 0, 0");
+        try {
+            stat.execute("truncate table parent");
+            fail();
+        } catch (SQLException e) {
+            // expected
+        }
+        try {
+            stat.execute("delete from parent");
+            fail();
+        } catch (SQLException e) {
+            // expected
+        }
+        stat.execute("alter table parent set referential_integrity false");
+        stat.execute("delete from parent");
+        stat.execute("truncate table parent");
+        stat.execute("alter table parent set referential_integrity true");
+        try {
+            stat.execute("truncate table parent");
+            fail();
+        } catch (SQLException e) {
+            // expected
+        }
+        stat.execute("set referential_integrity false");
+        stat.execute("truncate table parent");
+        conn.close();
+    }
+
     private void testPreparedSubquery2() throws SQLException {
         deleteDb("cases");
         Connection conn = getConnection("cases");