Column constraints are also visible in views (patch from Nicolas Fortin for H2GIS).

h2/src/docsrc/html/changelog.html

@@ -18,7 +18,8 @@ Change Log
 <h1>Change Log</h1>
 
 <h2>Next Version (unreleased)</h2>
-<ul><li>Granting a additional right to a role that already had a right for that table was not working.
+<ul><li>Column constraints are also visible in views (patch from Nicolas Fortin for H2GIS).
+</li><li>Granting a additional right to a role that already had a right for that table was not working.
 </li><li>Spatial index: a few bugs have been fixed (using spatial constraints in views,
     transferring geometry objects over TCP/IP).
 </li><li>Issue 551: the datatype documentation was incorrect (found by Bernd Eckenfels).

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

@@ -16,7 +16,9 @@ import org.h2.engine.Constants;
 import org.h2.engine.DbObject;
 import org.h2.engine.Session;
 import org.h2.engine.User;
+import org.h2.expression.Alias;
 import org.h2.expression.Expression;
+import org.h2.expression.ExpressionColumn;
 import org.h2.expression.ExpressionVisitor;
 import org.h2.expression.Parameter;
 import org.h2.index.Index;
@@ -39,6 +41,8 @@ import org.h2.value.Value;
 
 /**
  * A view is a virtual table that is defined by a query.
+ * @author Thomas Mueller
+ * @author Nicolas Fortin, Atelier SIG, IRSTV FR CNRS 24888
  */
 public class TableView extends Table {
 
@@ -168,6 +172,23 @@ public class TableView extends Table {
                 int displaySize = expr.getDisplaySize();
                 Column col = new Column(name, type, precision, scale, displaySize);
                 col.setTable(this, i);
+                // Fetch check constraint from view column source
+                ExpressionColumn fromColumn = null;
+                if (expr instanceof ExpressionColumn) {
+                    fromColumn = (ExpressionColumn) expr;
+                } else if (expr instanceof Alias) {
+                    Expression aliasExpr = expr.getNonAliasExpression();
+                    if (aliasExpr instanceof ExpressionColumn) {
+                        fromColumn = (ExpressionColumn) aliasExpr;
+                    }
+                }
+                if (fromColumn != null) {
+                    Expression checkExpression = fromColumn.getColumn()
+                            .getCheckConstraint(session, name);
+                    if (checkExpression != null) {
+                        col.addCheckConstraint(session, checkExpression);
+                    }
+                }
                 list.add(col);
             }
             cols = new Column[list.size()];

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

@@ -43,6 +43,7 @@ public class TestView extends TestBase {
         testManyViews();
         testReferenceView();
         testViewAlterAndCommandCache();
+        testViewConstraintFromColumnExpression();
         deleteDb("view");
     }
 
@@ -236,4 +237,45 @@ public class TestView extends TestBase {
         deleteDb("view");
     }
 
+    /**
+     * Make sure that the table constraint is still available when create a view of other table.
+     */
+    private void testViewConstraintFromColumnExpression() throws SQLException {
+        deleteDb("view");
+        Connection conn = getConnection("view");
+        Statement stat = conn.createStatement();
+        stat.execute("create table t0(id1 int primary key CHECK ((ID1 % 2) = 0))");
+        stat.execute("create table t1(id2 int primary key CHECK ((ID2 % 1) = 0))");
+        stat.execute("insert into t0 values(0)");
+        stat.execute("insert into t1 values(1)");
+        stat.execute("create view v1 as select * from t0,t1");
+        // Check with ColumnExpression
+        ResultSet rs = stat.executeQuery("select * from INFORMATION_SCHEMA.COLUMNS where TABLE_NAME = 'V1'");
+        assertTrue(rs.next());
+        assertEquals("ID1", rs.getString("COLUMN_NAME"));
+        assertEquals("((ID1 % 2) = 0)", rs.getString("CHECK_CONSTRAINT"));
+        assertTrue(rs.next());
+        assertEquals("ID2", rs.getString("COLUMN_NAME"));
+        assertEquals("((ID2 % 1) = 0)", rs.getString("CHECK_CONSTRAINT"));
+        // Check with AliasExpression
+        stat.execute("create view v2 as select ID1 key1,ID2 key2 from t0,t1");
+        rs = stat.executeQuery("select * from INFORMATION_SCHEMA.COLUMNS where TABLE_NAME = 'V2'");
+        assertTrue(rs.next());
+        assertEquals("KEY1", rs.getString("COLUMN_NAME"));
+        assertEquals("((KEY1 % 2) = 0)", rs.getString("CHECK_CONSTRAINT"));
+        assertTrue(rs.next());
+        assertEquals("KEY2", rs.getString("COLUMN_NAME"));
+        assertEquals("((KEY2 % 1) = 0)", rs.getString("CHECK_CONSTRAINT"));
+        // Check hide of constraint if column is an Operation
+        stat.execute("create view v3 as select ID1 + 1 ID1, ID2 + 1 ID2 from t0,t1");
+        rs = stat.executeQuery("select * from INFORMATION_SCHEMA.COLUMNS where TABLE_NAME = 'V3'");
+        assertTrue(rs.next());
+        assertEquals("ID1", rs.getString("COLUMN_NAME"));
+        assertEquals("", rs.getString("CHECK_CONSTRAINT"));
+        assertTrue(rs.next());
+        assertEquals("ID2", rs.getString("COLUMN_NAME"));
+        assertEquals("", rs.getString("CHECK_CONSTRAINT"));
+        conn.close();
+        deleteDb("view");
+    }
 }