Fix updateRow when there are primary keys and unique keys, PR pgjdbc#…

…2199 made some incorrect assumptions about unique keys that were incorrect.

When we have both primary keys and unique keys only use the Primary keys for updating the row.

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

@@ -2182,7 +2182,7 @@ protected ResultSet getPrimaryUniqueKeys(@Nullable String catalog, @Nullable Str
     sql = "SELECT NULL AS TABLE_CAT, n.nspname AS TABLE_SCHEM, "
         + "  ct.relname AS TABLE_NAME, a.attname AS COLUMN_NAME, "
         + "  (information_schema._pg_expandarray(i.indkey)).n AS KEY_SEQ, ci.relname AS PK_NAME, "
-        + "  information_schema._pg_expandarray(i.indkey) AS KEYS, a.attnum AS A_ATTNUM "
+        + "  information_schema._pg_expandarray(i.indkey) AS KEYS, a.attnum AS A_ATTNUM, i.indisprimary AS IS_PRIMARY "
         + "FROM pg_catalog.pg_class ct "
         + "  JOIN pg_catalog.pg_attribute a ON (ct.oid = a.attrelid) "
         + "  JOIN pg_catalog.pg_namespace n ON (ct.relnamespace = n.oid) "
@@ -2205,7 +2205,8 @@ protected ResultSet getPrimaryUniqueKeys(@Nullable String catalog, @Nullable Str
         + "       result.TABLE_NAME, "
         + "       result.COLUMN_NAME, "
         + "       result.KEY_SEQ, "
-        + "       result.PK_NAME "
+        + "       result.PK_NAME, "
+        + "       result.IS_PRIMARY "
         + "FROM "
         + "     (" + sql + " ) result"
         + " where "

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

@@ -1418,6 +1418,10 @@ public synchronized void updateRow() throws SQLException {
     List<PrimaryKey> primaryKeys = castNonNull(this.primaryKeys, "primaryKeys");
     int numKeys = primaryKeys.size();
 
+    // since we now return both primary and unique keys in order to optimize finding unique keys to
+    // use in updateRow we want to know if we are using primary keys or unique keys to do the update
+    // primary keys cannot be null, unique keys can. If we have a primary key then we don't need
+    // the unique keys. If we have no primary keys then we have to handle null unique keys.
     for (int i = 0; i < numKeys; i++) {
       PrimaryKey primaryKey = primaryKeys.get(i);
       Utils.escapeIdentifier(updateSQL, primaryKey.name);
@@ -1634,10 +1638,34 @@ boolean isUpdateable() throws SQLException {
       /* make sure that the user has included the primary key in the resultset */
       if (index > 0) {
         i++;
-        primaryKeys.add(new PrimaryKey(index, columnName)); // get the primary key information
+        primaryKeys.add(new PrimaryKey(index, columnName, rs.getBoolean("IS_PRIMARY"))); // get the primary key information
       }
     }
 
+    // look to see if we have primary keys, if we do remove the unique keys, we added them so they could be used without any primary keys
+    // this is convoluted but easier to do in java than in SQL.
+
+    boolean usingPrimaryKeys = false;
+    for ( int j = 0; j < i; j++ ) {
+      if (primaryKeys.get(j).isPrimary) {
+        usingPrimaryKeys = true;
+      }
+    }
+
+    if ( usingPrimaryKeys ) {
+      boolean uniqueKeys = false;
+      do  {
+        for (int j = 0; j < i; j++) {
+          if (!primaryKeys.get(j).isPrimary) {
+            primaryKeys.remove(j);
+            uniqueKeys = true;
+            i--;
+            numPKcolumns--;
+            break;
+          }
+        }
+      } while ( uniqueKeys );
+    }
     rs.close();
     connection.getLogger().log(Level.FINE, "no of keys={0}", i);
 
@@ -1658,7 +1686,7 @@ boolean isUpdateable() throws SQLException {
 
       // oidIndex will be >0 if the oid was in the select list
       if (oidIndex > 0) {
-        primaryKeys.add(new PrimaryKey(oidIndex, "oid"));
+        primaryKeys.add(new PrimaryKey(oidIndex, "oid", true));
         usingOID = true;
         updateable = true;
       }
@@ -3293,10 +3321,12 @@ protected Object getUUID(byte[] data) throws SQLException {
   private class PrimaryKey {
     int index; // where in the result set is this primaryKey
     String name; // what is the columnName of this primary Key
+    boolean isPrimary; // in order to allow unique keys to be used for updating rows we include them as primary keys
 
-    PrimaryKey(int index, String name) {
+    PrimaryKey(int index, String name, boolean isPrimary) {
       this.index = index;
       this.name = name;
+      this.isPrimary = isPrimary;
     }
 
     @Nullable Object getValue() throws SQLException {

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

@@ -23,13 +23,7 @@
 import java.io.ByteArrayInputStream;
 import java.io.StringReader;
 import java.io.UnsupportedEncodingException;
-import java.sql.Array;
-import java.sql.PreparedStatement;
-import java.sql.ResultSet;
-import java.sql.SQLException;
-import java.sql.Statement;
-import java.sql.Timestamp;
-import java.sql.Types;
+import java.sql.*;
 import java.util.TimeZone;
 
 public class UpdateableResultTest extends BaseTest4 {
@@ -39,6 +33,7 @@ public void setUp() throws Exception {
     super.setUp();
     TestUtil.createTable(con, "updateable",
         "id int primary key, name text, notselected text, ts timestamp with time zone, intarr int[]");
+    TestUtil.createTable(con, "hasdate", "id int primary key, dt date unique, name text");
     TestUtil.createTable(con, "second", "id1 int primary key, name1 text");
     TestUtil.createTable(con, "serialtable", "gen_id serial primary key, name text");
     TestUtil.createTable(con, "compositepktable", "gen_id serial, name text, dec_id serial");
@@ -71,6 +66,7 @@ public void tearDown() throws SQLException {
     TestUtil.dropTable(con, "nopkmulticol");
     TestUtil.dropTable(con, "booltable");
     TestUtil.dropTable(con, "uniqueconstraint");
+    TestUtil.dropTable(con, "hasdate");
     super.tearDown();
   }
 
@@ -447,6 +443,26 @@ public void testUpdateable() throws SQLException {
     st.close();
   }
 
+  @Test
+  public void testUpdateDate() throws Exception{
+    Date testDate = Date.valueOf("2021-01-01");
+    TestUtil.execute( "insert into hasdate values (1,'2021-01-01'::date)", con);
+    con.setAutoCommit(false);
+    String sql = "SELECT * FROM hasdate where id=1";
+    ResultSet rs = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE ).executeQuery(sql);
+    assertTrue(rs.next());
+    assertEquals(testDate, rs.getDate("dt"));
+    rs.updateDate("dt", Date.valueOf("2020-01-01"));
+    rs.updateRow();
+    assertEquals(Date.valueOf("2020-01-01"), rs.getDate("dt"));
+    System.out.println("After Update: " + rs.getDate("dt"));
+    con.commit();
+    rs = con.createStatement().executeQuery("select dt from hasdate where id=1");
+    assertTrue(rs.next());
+    assertEquals(Date.valueOf("2020-01-01"), rs.getDate("dt"));
+    rs.close();
+  }
+
   @Test
   public void test2193() throws Exception {
     Statement st =