METR-20494: expose name->columnNum metadata

src/main/java/ru/yandex/metrika/clickhouse/CHStatementImpl.java

@@ -125,12 +125,15 @@ public class CHStatementImpl implements CHStatement {
 
     @Override
     public boolean execute(String sql) throws SQLException {
-        executeQuery(sql);
+        ResultSet rs = null;
+        try {
+            rs = executeQuery(sql);
+        } finally {
+            CopypasteUtils.close(rs);
+        }
         return true;
     }
 
-
-
     @Override
     public void close() throws SQLException {
         if (currentResult != null) {

src/main/java/ru/yandex/metrika/clickhouse/copypaste/CHResultSet.java

@@ -127,7 +127,7 @@ public class CHResultSet extends AbstractResultSet {
         return columns;
     }
 
-    Map<String, Integer> getCol() {
+    public Map<String, Integer> getCol() {
         return col;
     }
 
@@ -440,4 +440,8 @@ public class CHResultSet extends AbstractResultSet {
     public <T> T getObject(String columnLabel, Class<T> type) throws SQLException {
         return getObject(asColNum(columnLabel), type);
     }
+
+    public ByteFragment[] getValues() {
+        return values;
+    }
 }