diff --git a/jdbc-query/src/main/java/org/xbib/jdbc/query/DatabaseImpl.java b/jdbc-query/src/main/java/org/xbib/jdbc/query/DatabaseImpl.java
index a68e286..b2a93af 100644
--- a/jdbc-query/src/main/java/org/xbib/jdbc/query/DatabaseImpl.java
+++ b/jdbc-query/src/main/java/org/xbib/jdbc/query/DatabaseImpl.java
@@ -10,9 +10,7 @@ import java.time.Duration;
 import java.time.LocalDateTime;
 import java.time.format.DateTimeFormatter;
 import java.util.HashMap;
-import java.util.Locale;
 import java.util.Map;
-import java.util.logging.Level;
 import java.util.logging.Logger;
 
 /**
@@ -237,15 +235,14 @@ public class DatabaseImpl implements Database {
                 int cols = rsmd.getColumnCount();
                 while (rs.next()) {
                     String name = "";
-                    Integer size = 0;
+                    int size = 0;
                     for (int i = 1; i <= cols; i++) {
                         String label = rsmd.getColumnName(i);
-                        Object v = rs.getObject(i);
-                        if (label.equals("COLUMN_NAME")) {
-                            name = (String) v;
+                        if ("COLUMN_NAME".equalsIgnoreCase(label)) {
+                            name = rs.getString(i);
                         }
-                        if (label.equals("COLUMN_SIZE")) {
-                            size = (Integer) v;
+                        if ("COLUMN_SIZE".equalsIgnoreCase(label)) {
+                            size = rs.getBigDecimal(i).intValue();
                         }
                     }
                     map.put(name, size);
diff --git a/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlInsert.java b/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlInsert.java
index ccdfecd..f712da6 100644
--- a/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlInsert.java
+++ b/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlInsert.java
@@ -49,27 +49,29 @@ public interface SqlInsert {
 
     SqlInsert argDateNowPerApp();
 
-    SqlInsert argDateNowPerApp( String argName);
+    SqlInsert argDateNowPerApp(String argName);
 
     SqlInsert argDateNowPerDb();
 
-    SqlInsert argDateNowPerDb( String argName);
+    SqlInsert argDateNowPerDb(String argName);
 
     SqlInsert argBlobBytes(byte[] arg);
 
-    SqlInsert argBlobBytes( String argName, byte[] arg);
+    SqlInsert argBlobBytes(String argName, byte[] arg);
 
     SqlInsert argBlobStream(InputStream arg);
 
-    SqlInsert argBlobStream( String argName, InputStream arg);
+    SqlInsert argBlobStream(String argName, InputStream arg);
 
     SqlInsert argClobString(String arg);
 
-    SqlInsert argClobString( String argName, String arg);
+    SqlInsert argClobString(String argName, String arg);
 
     SqlInsert argClobReader(Reader arg);
 
-    SqlInsert argClobReader( String argName, Reader arg);
+    SqlInsert argClobReader(String argName, Reader arg);
+
+    SqlInsert argNull(String argName);
 
     SqlInsert withArgs(SqlArgs args);
 
diff --git a/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlInsertImpl.java b/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlInsertImpl.java
index 09db1fd..53a75c1 100644
--- a/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlInsertImpl.java
+++ b/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlInsertImpl.java
@@ -1,5 +1,6 @@
 package org.xbib.jdbc.query;
 
+import java.sql.Types;
 import org.xbib.jdbc.query.util.DebugSql;
 import org.xbib.jdbc.query.util.InternalStringReader;
 import org.xbib.jdbc.query.util.Metric;
@@ -158,7 +159,6 @@ public class SqlInsertImpl implements SqlInsert {
     public SqlInsert argLocalDate(LocalDate arg) {
         return positionalArg(adaptor.nullLocalDate(arg));
     }
-
     
     @Override
     public SqlInsert argDateNowPerApp() {
@@ -179,7 +179,6 @@ public class SqlInsertImpl implements SqlInsert {
     }
 
     @Override
-    
     public SqlInsert argDateNowPerDb( String argName) {
         if (options.useDatePerAppOnly()) {
             return namedArg(argName, adaptor.nullDate(options.currentDate()));
@@ -188,54 +187,50 @@ public class SqlInsertImpl implements SqlInsert {
     }
 
     @Override
-    
     public SqlInsert argBlobBytes(byte[] arg) {
         return positionalArg(adaptor.nullBytes(arg));
     }
 
     @Override
-    
     public SqlInsert argBlobBytes( String argName, byte[] arg) {
         return namedArg(argName, adaptor.nullBytes(arg));
     }
 
     @Override
-    
     public SqlInsert argBlobStream(InputStream arg) {
         return positionalArg(adaptor.nullInputStream(arg));
     }
 
     @Override
-    
     public SqlInsert argBlobStream( String argName, InputStream arg) {
         return namedArg(argName, adaptor.nullInputStream(arg));
     }
 
     @Override
-    
     public SqlInsert argClobString(String arg) {
         return positionalArg(adaptor.nullClobReader(arg == null ? null : new InternalStringReader(arg)));
     }
 
     @Override
-    
     public SqlInsert argClobString( String argName, String arg) {
         return namedArg(argName, adaptor.nullClobReader(arg == null ? null : new InternalStringReader(arg)));
     }
 
     @Override
-    
     public SqlInsert argClobReader(Reader arg) {
         return positionalArg(adaptor.nullClobReader(arg));
     }
 
     @Override
-    
     public SqlInsert argClobReader( String argName, Reader arg) {
         return namedArg(argName, adaptor.nullClobReader(arg));
     }
 
-    
+    @Override
+    public SqlInsert argNull(String argName) {
+        return namedArg(argName, new SqlNull(Types.VARCHAR));
+    }
+
     @Override
     public SqlInsert withArgs(SqlArgs args) {
         return apply(args);
diff --git a/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlUpdate.java b/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlUpdate.java
index a20f90f..868f58b 100644
--- a/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlUpdate.java
+++ b/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlUpdate.java
@@ -13,64 +13,66 @@ public interface SqlUpdate {
     
     SqlUpdate argBoolean(Boolean arg);
     
-    SqlUpdate argBoolean( String argName, Boolean arg);
+    SqlUpdate argBoolean(String argName, Boolean arg);
     
     SqlUpdate argInteger(Integer arg);
     
-    SqlUpdate argInteger( String argName, Integer arg);
+    SqlUpdate argInteger(String argName, Integer arg);
     
     SqlUpdate argLong(Long arg);
     
-    SqlUpdate argLong( String argName, Long arg);
+    SqlUpdate argLong(String argName, Long arg);
     
     SqlUpdate argFloat(Float arg);
     
-    SqlUpdate argFloat( String argName, Float arg);
+    SqlUpdate argFloat(String argName, Float arg);
     
     SqlUpdate argDouble(Double arg);
     
-    SqlUpdate argDouble( String argName, Double arg);
+    SqlUpdate argDouble(String argName, Double arg);
     
     SqlUpdate argBigDecimal(BigDecimal arg);
 
-    SqlUpdate argBigDecimal( String argName, BigDecimal arg);
+    SqlUpdate argBigDecimal(String argName, BigDecimal arg);
     
     SqlUpdate argString(String arg);
     
-    SqlUpdate argString( String argName, String arg);
+    SqlUpdate argString(String argName, String arg);
     
     SqlUpdate argDate(LocalDateTime arg);
     
-    SqlUpdate argDate( String argName, LocalDateTime arg);
+    SqlUpdate argDate(String argName, LocalDateTime arg);
 
     SqlUpdate argLocalDate(LocalDate arg);
 
-    SqlUpdate argLocalDate( String argName, LocalDate arg);
+    SqlUpdate argLocalDate(String argName, LocalDate arg);
 
     SqlUpdate argDateNowPerApp();
     
-    SqlUpdate argDateNowPerApp( String argName);
+    SqlUpdate argDateNowPerApp(String argName);
 
     SqlUpdate argDateNowPerDb();
 
-    SqlUpdate argDateNowPerDb( String argName);
+    SqlUpdate argDateNowPerDb(String argName);
 
     SqlUpdate argBlobBytes(byte[] arg);
 
-    SqlUpdate argBlobBytes( String argName, byte[] arg);
+    SqlUpdate argBlobBytes(String argName, byte[] arg);
 
     SqlUpdate argBlobStream(InputStream arg);
 
-    SqlUpdate argBlobStream( String argName, InputStream arg);
+    SqlUpdate argBlobStream(String argName, InputStream arg);
 
     SqlUpdate argClobString(String arg);
 
-    SqlUpdate argClobString( String argName, String arg);
+    SqlUpdate argClobString(String argName, String arg);
 
     SqlUpdate argClobReader(Reader arg);
 
-    SqlUpdate argClobReader( String argName, Reader arg);
-    
+    SqlUpdate argClobReader(String argName, Reader arg);
+
+    SqlUpdate argNull(String argName);
+
     SqlUpdate withArgs(SqlArgs args);
     
     SqlUpdate apply(Apply apply);
diff --git a/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlUpdateImpl.java b/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlUpdateImpl.java
index 822d34a..cfcc558 100644
--- a/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlUpdateImpl.java
+++ b/jdbc-query/src/main/java/org/xbib/jdbc/query/SqlUpdateImpl.java
@@ -1,5 +1,6 @@
 package org.xbib.jdbc.query;
 
+import java.sql.Types;
 import org.xbib.jdbc.query.util.DebugSql;
 import org.xbib.jdbc.query.util.InternalStringReader;
 import org.xbib.jdbc.query.util.Metric;
@@ -229,7 +230,11 @@ public class SqlUpdateImpl implements SqlUpdate {
         return namedArg(argName, adaptor.nullClobReader(arg));
     }
 
-    
+    @Override
+    public SqlUpdate argNull(String argName) {
+        return namedArg(argName, new SqlNull(Types.VARCHAR));
+    }
+
     @Override
     public SqlUpdate withArgs(SqlArgs args) {
         return apply(args);