DROP TABLE RESTRICT shouldn't drop foreign constraints

h2/src/docsrc/help/help.csv

@@ -907,8 +907,8 @@ DROP SEQUENCE SEQ_ID
 DROP TABLE [ IF EXISTS ] tableName [,...] [ RESTRICT | CASCADE ]
 ","
 Drops an existing table, or a list of tables.
-The command will fail if dependent views exist and the RESTRICT clause is used (the default).
-All dependent views are dropped as well if the CASCADE clause is used.
+The command will fail if dependent objects exist and the RESTRICT clause is used (the default).
+All dependent views and constraints are dropped as well if the CASCADE clause is used.
 This command commits an open transaction in this connection.
 ","
 DROP TABLE TEST

h2/src/main/org/h2/command/ddl/DropTable.java

@@ -5,9 +5,12 @@
  */
 package org.h2.command.ddl;
 
+import java.util.List;
 import java.util.concurrent.CopyOnWriteArrayList;
+
 import org.h2.api.ErrorCode;
 import org.h2.command.CommandInterface;
+import org.h2.constraint.Constraint;
 import org.h2.constraint.ConstraintReferential;
 import org.h2.engine.Database;
 import org.h2.engine.Right;
@@ -73,15 +76,26 @@ public class DropTable extends SchemaCommand {
                 throw DbException.get(ErrorCode.CANNOT_DROP_TABLE_1, tableName);
             }
             if (dropAction == ConstraintReferential.RESTRICT) {
+                StatementBuilder buff = new StatementBuilder();
                 CopyOnWriteArrayList<TableView> dependentViews = table.getDependentViews();
                 if (dependentViews != null && dependentViews.size() > 0) {
-                    StatementBuilder buff = new StatementBuilder();
                     for (TableView v : dependentViews) {
                         buff.appendExceptFirst(", ");
                         buff.append(v.getName());
                     }
-                    throw DbException.get(ErrorCode.CANNOT_DROP_2, tableName, buff.toString());
                 }
+                final List<Constraint> constraints = table.getConstraints();
+                if (constraints != null && constraints.size() > 0) {
+                    for (Constraint c : constraints) {
+                        if (c.getTable() != table) {
+                            buff.appendExceptFirst(", ");
+                            buff.append(c.getName());
+                        }
+                    }
+                }
+                if (buff.length() > 0)
+                    throw DbException.get(ErrorCode.CANNOT_DROP_2, tableName, buff.toString());
+
             }
             table.lock(session, true, true);
         }

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

@@ -54,6 +54,7 @@ public class TestCases extends TestBase {
         testGroupSubquery();
         testCountDistinctNotNull();
         testDependencies();
+        testDropTable();
         testConvertType();
         testSortedSelect();
         testMaxMemoryRows();
@@ -278,6 +279,53 @@ public class TestCases extends TestBase {
         conn.close();
     }
 
+    private static enum DropDependent {
+        NONE, VIEW, FOREIGN_KEY;
+    }
+
+    private void testDropTable() throws SQLException {
+        trace("testDrop");
+
+        for (final boolean restrict : new boolean[] { true, false }) {
+            for (final DropDependent dropDep : DropDependent.values()) {
+                deleteDb("cases");
+                Connection conn = getConnection("cases");
+                Statement stat = conn.createStatement();
+                stat.execute("create table test(id int)");
+                if (dropDep == DropDependent.VIEW) {
+                    stat.execute("create view abc as select * from test");
+                } else if (dropDep == DropDependent.FOREIGN_KEY) {
+                    stat.execute("create table ref(id int, id_test int, foreign key (id_test) references test (id)) ");
+                    // test table is empty so the foreign key forces ref table to be also empty
+                    assertThrows(ErrorCode.REFERENTIAL_INTEGRITY_VIOLATED_PARENT_MISSING_1, stat).execute("insert into ref values(1,2)");
+                }
+
+                // drop allowed if no references or cascade
+                final boolean expectedDropSuccess = dropDep == DropDependent.NONE || !restrict;
+                assertThrows(expectedDropSuccess ? 0 : ErrorCode.CANNOT_DROP_2, stat).execute("drop table test " + (restrict ? "restrict" : "cascade"));
+                assertThrows(expectedDropSuccess ? ErrorCode.TABLE_OR_VIEW_NOT_FOUND_1 : 0, stat).execute("select * from test");
+
+                // missing view if it was never created or if the drop succeeded
+                assertThrows(dropDep != DropDependent.VIEW || expectedDropSuccess ? ErrorCode.TABLE_OR_VIEW_NOT_FOUND_1 : 0, stat).execute("select * from abc");
+
+                final int refError;
+                if (dropDep != DropDependent.FOREIGN_KEY) {
+                    // never created
+                    refError = ErrorCode.TABLE_OR_VIEW_NOT_FOUND_1;
+                } else if (expectedDropSuccess) {
+                    // foreign key dropped
+                    refError = 0;
+                } else {
+                    // foreign key not dropped
+                    refError = ErrorCode.REFERENTIAL_INTEGRITY_VIOLATED_PARENT_MISSING_1;
+                }
+                assertThrows(refError, stat).execute("insert into ref values(1,2)");
+
+                conn.close();
+            }
+        }
+    }
+
     private void testConvertType() throws SQLException {
         deleteDb("cases");
         Connection conn = getConnection("cases");