feat: add smallserial metadata (pgjdbc#899)

PostgreSQL 9.2 adds a SMALLSERIAL data type, this reports the correct metadata information when a column is a smallserial (int2 with sequence), similar to how a serial or bigserial data types are reported.

pgjdbc/src/main/java/org/postgresql/jdbc/PgDatabaseMetaData.java

@@ -1609,7 +1609,7 @@ public ResultSet getColumns(@Nullable String catalog, @Nullable String schemaPat
           tuple[5] = connection.encodeString("serial"); // Type name == serial
         } else if ("int8".equals(pgType)) {
           tuple[5] = connection.encodeString("bigserial"); // Type name == bigserial
-        } else if ("int2".equals(pgType)) {
+        } else if ("int2".equals(pgType) && connection.haveMinimumServerVersion(ServerVersion.v9_2)) {
           tuple[5] = connection.encodeString("smallserial"); // Type name == smallserial
         }
       }
@@ -2372,19 +2372,25 @@ public ResultSet getTypeInfo() throws SQLException {
       tuple[17] = b10; // everything is base 10
       v.add(new Tuple(tuple));
 
-      // add pseudo-type serial, bigserial
-      if (typname.equals("int4")) {
+      // add pseudo-type serial, bigserial, smallserial
+      if ("int4".equals(typname)) {
         byte[] @Nullable [] tuple1 = tuple.clone();
 
         tuple1[0] = connection.encodeString("serial");
         tuple1[11] = bt;
         v.add(new Tuple(tuple1));
-      } else if (typname.equals("int8")) {
+      } else if ("int8".equals(typname)) {
         byte[] @Nullable [] tuple1 = tuple.clone();
 
         tuple1[0] = connection.encodeString("bigserial");
         tuple1[11] = bt;
         v.add(new Tuple(tuple1));
+      } else if ("int2".equals(typname) && connection.haveMinimumServerVersion(ServerVersion.v9_2)) {
+        byte[] @Nullable [] tuple1 = tuple.clone();
+
+        tuple1[0] = connection.encodeString("smallserial");
+        tuple1[11] = bt;
+        v.add(new Tuple(tuple1));
       }
 
     }

pgjdbc/src/main/java/org/postgresql/jdbc/PgResultSetMetaData.java

@@ -328,6 +328,8 @@ public String getColumnTypeName(int column) throws SQLException {
         return "serial";
       } else if ("int8".equals(type)) {
         return "bigserial";
+      } else if ("int2".equals(type) && connection.haveMinimumServerVersion(ServerVersion.v9_2)) {
+        return "smallserial";
       }
     }
 

pgjdbc/src/test/java/org/postgresql/test/jdbc2/DatabaseMetaDataTest.java

@@ -75,8 +75,7 @@ public void setUp() throws Exception {
         "id int4, name text, updated timestamptz, colour text, quest text");
     TestUtil.dropSequence(con, "sercoltest_b_seq");
     TestUtil.dropSequence(con, "sercoltest_c_seq");
-    TestUtil.dropSequence(con, "sercoltest_s_seq");
-    TestUtil.createTable(con, "sercoltest", "a int, b serial, c bigserial, s smallserial");
+    TestUtil.createTable(con, "sercoltest", "a int, b serial, c bigserial");
     TestUtil.createTable(con, "\"a\\\"", "a int4");
     TestUtil.createTable(con, "\"a'\"", "a int4");
     TestUtil.createTable(con, "arraytable", "a numeric(5,2)[], b varchar(100)[]");
@@ -129,7 +128,6 @@ public void tearDown() throws Exception {
     TestUtil.dropTable(con, "sercoltest");
     TestUtil.dropSequence(con, "sercoltest_b_seq");
     TestUtil.dropSequence(con, "sercoltest_c_seq");
-    TestUtil.dropSequence(con, "sercoltest_s_seq");
     TestUtil.dropTable(con, "\"a\\\"");
     TestUtil.dropTable(con, "\"a'\"");
     TestUtil.dropTable(con, "arraytable");
@@ -583,14 +581,11 @@ public void testSerialColumns() throws SQLException {
       } else if (rownum == 2) {
         assertEquals("bigserial", rs.getString("TYPE_NAME"));
         assertTrue(rs.getBoolean("IS_AUTOINCREMENT"));
-      } else if (rownum == 3 ) {
-        assertEquals("smallserial", rs.getString("TYPE_NAME"));
-        assertTrue(rs.getBoolean("IS_AUTOINCREMENT"));
       }
 
       rownum++;
     }
-    assertEquals(4, rownum);
+    assertEquals(3, rownum);
     rs.close();
   }
 
@@ -1493,4 +1488,56 @@ public void testFunctionColumns() throws SQLException {
 
     rs.close();
   }
+
+  @Test
+  public void testSmallSerialColumns() throws SQLException {
+    org.junit.Assume.assumeTrue(TestUtil.haveMinimumServerVersion(con, ServerVersion.v9_2));
+    TestUtil.createTable(con, "smallserial_test", "a smallserial");
+
+    DatabaseMetaData dbmd = con.getMetaData();
+    ResultSet rs = dbmd.getColumns(null, null, "smallserial_test", "a");
+    assertTrue(rs.next());
+    assertEquals("smallserial_test", rs.getString("TABLE_NAME"));
+    assertEquals("a", rs.getString("COLUMN_NAME"));
+    assertEquals(Types.SMALLINT, rs.getInt("DATA_TYPE"));
+    assertEquals("smallserial", rs.getString("TYPE_NAME"));
+    assertTrue(rs.getBoolean("IS_AUTOINCREMENT"));
+    assertEquals("nextval('smallserial_test_a_seq'::regclass)", rs.getString("COLUMN_DEF"));
+    assertFalse(rs.next());
+    rs.close();
+
+    TestUtil.dropTable(con, "smallserial_test");
+  }
+
+  @Test
+  public void testSmallSerialSequenceLikeColumns() throws SQLException {
+    Statement stmt = con.createStatement();
+    // This is the equivalent of the smallserial, not the actual smallserial
+    stmt.execute("CREATE SEQUENCE smallserial_test_a_seq;\n"
+        + "CREATE TABLE smallserial_test (\n"
+        + "    a smallint NOT NULL DEFAULT nextval('smallserial_test_a_seq')\n"
+        + ");\n"
+        + "ALTER SEQUENCE smallserial_test_a_seq OWNED BY smallserial_test.a;");
+
+    DatabaseMetaData dbmd = con.getMetaData();
+    ResultSet rs = dbmd.getColumns(null, null, "smallserial_test", "a");
+    assertTrue(rs.next());
+    assertEquals("smallserial_test", rs.getString("TABLE_NAME"));
+    assertEquals("a", rs.getString("COLUMN_NAME"));
+    assertEquals(Types.SMALLINT, rs.getInt("DATA_TYPE"));
+    if (TestUtil.haveMinimumServerVersion(con, ServerVersion.v9_2)) {
+      // in Pg 9.2+ it behaves like smallserial
+      assertEquals("smallserial", rs.getString("TYPE_NAME"));
+    } else {
+      assertEquals("int2", rs.getString("TYPE_NAME"));
+    }
+    assertTrue(rs.getBoolean("IS_AUTOINCREMENT"));
+    assertEquals("nextval('smallserial_test_a_seq'::regclass)", rs.getString("COLUMN_DEF"));
+    assertFalse(rs.next());
+    rs.close();
+
+    stmt.execute("DROP TABLE smallserial_test");
+    stmt.close();
+  }
+
 }

pgjdbc/src/test/java/org/postgresql/test/jdbc2/ResultSetMetaDataTest.java

@@ -340,4 +340,50 @@ private void assumePreparedStatementMetadataSupported() {
         preferQueryMode.compareTo(PreferQueryMode.EXTENDED_FOR_PREPARED) >= 0);
   }
 
+  @Test
+  public void testSmallSerialColumns() throws SQLException {
+    org.junit.Assume.assumeTrue(TestUtil.haveMinimumServerVersion(con, ServerVersion.v9_2));
+    TestUtil.createTable(con, "smallserial_test", "a smallserial");
+
+    Statement stmt = conn.createStatement();
+    ResultSet rs = stmt.executeQuery("SELECT a FROM smallserial_test");
+    ResultSetMetaData rsmd = rs.getMetaData();
+    assertTrue(rsmd.isAutoIncrement(1));
+    assertEquals("smallserial_test", rsmd.getTableName(1));
+    assertEquals("a", rsmd.getColumnName(1));
+    assertEquals(Types.SMALLINT, rsmd.getColumnType(1));
+    assertEquals("smallserial", rsmd.getColumnTypeName(1));
+    rs.close();
+
+    TestUtil.dropTable(con, "smallserial_test");
+  }
+
+  @Test
+  public void testSmallSerialSequenceLikeColumns() throws SQLException {
+    Statement stmt = con.createStatement();
+    // This is the equivalent of the smallserial, not the actual smallserial
+    stmt.execute("CREATE SEQUENCE smallserial_test_a_seq;\n"
+        + "CREATE TABLE smallserial_test (\n"
+        + "    a smallint NOT NULL DEFAULT nextval('smallserial_test_a_seq')\n"
+        + ");\n"
+        + "ALTER SEQUENCE smallserial_test_a_seq OWNED BY smallserial_test.a;");
+
+    ResultSet rs = stmt.executeQuery("SELECT a FROM smallserial_test");
+    ResultSetMetaData rsmd = rs.getMetaData();
+    assertTrue(rsmd.isAutoIncrement(1));
+    assertEquals("smallserial_test", rsmd.getTableName(1));
+    assertEquals("a", rsmd.getColumnName(1));
+    assertEquals(Types.SMALLINT, rsmd.getColumnType(1));
+    if (TestUtil.haveMinimumServerVersion(con, ServerVersion.v9_2)) {
+      // in Pg 9.2+ it behaves like smallserial
+      assertEquals("smallserial", rsmd.getColumnTypeName(1));
+    } else {
+      assertEquals("int2", rsmd.getColumnTypeName(1));
+    }
+    rs.close();
+
+    stmt.execute("DROP TABLE smallserial_test");
+    stmt.close();
+  }
+
 }