diff --git a/src/main/java/fr/xephi/authme/datasource/MySQL.java b/src/main/java/fr/xephi/authme/datasource/MySQL.java
index a9908eb30..7a8d9fa69 100644
--- a/src/main/java/fr/xephi/authme/datasource/MySQL.java
+++ b/src/main/java/fr/xephi/authme/datasource/MySQL.java
@@ -268,9 +268,9 @@ public class MySQL extends AbstractSqlDataSource {
             if (isColumnMissing(md, col.TOTP_KEY)) {
                 st.executeUpdate("ALTER TABLE " + tableName
                     + " ADD COLUMN " + col.TOTP_KEY + " VARCHAR(32);");
-            } else if (isColumnSizeIncorrect(md, col.TOTP_KEY, 32)) {
+            } else if (SqlDataSourceUtils.getColumnSize(md, tableName, col.TOTP_KEY) != 32) {
                 st.executeUpdate("ALTER TABLE " + tableName
-                    + " ALTER COLUMN " + col.TOTP_KEY + " VARCHAR(32);");
+                    + " MODIFY " + col.TOTP_KEY + " VARCHAR(32);");
             }
 
             if (!col.PLAYER_UUID.isEmpty() && isColumnMissing(md, col.PLAYER_UUID)) {
@@ -287,16 +287,6 @@ public class MySQL extends AbstractSqlDataSource {
         }
     }
 
-    private boolean isColumnSizeIncorrect(DatabaseMetaData metaData, String columnName, int size) throws SQLException {
-        try (ResultSet rs = metaData.getColumns(null, null, tableName, columnName)) {
-            if (!rs.next()) {
-                throw new RuntimeException("Column " + columnName + " doesn't exist!");
-            }
-            int currentSize = rs.getInt("COLUMN_SIZE");
-            return size != currentSize;
-        }
-    }
-
     @Override
     public PlayerAuth getAuth(String user) {
         String sql = "SELECT * FROM " + tableName + " WHERE " + col.NAME + "=?;";
diff --git a/src/main/java/fr/xephi/authme/datasource/PostgreSqlDataSource.java b/src/main/java/fr/xephi/authme/datasource/PostgreSqlDataSource.java
index fddf3b650..b0186f4b7 100644
--- a/src/main/java/fr/xephi/authme/datasource/PostgreSqlDataSource.java
+++ b/src/main/java/fr/xephi/authme/datasource/PostgreSqlDataSource.java
@@ -243,9 +243,9 @@ public class PostgreSqlDataSource extends AbstractSqlDataSource {
             if (isColumnMissing(md, col.TOTP_KEY)) {
                 st.executeUpdate("ALTER TABLE " + tableName
                     + " ADD COLUMN " + col.TOTP_KEY + " VARCHAR(32);");
-            } else if (isColumnSizeIncorrect(md, col.TOTP_KEY, 32)) {
+            } else if (SqlDataSourceUtils.getColumnSize(md, tableName, col.TOTP_KEY) != 32) {
                 st.executeUpdate("ALTER TABLE " + tableName
-                    + " ALTER COLUMN " + col.TOTP_KEY + " VARCHAR(32);");
+                    + " ALTER COLUMN " + col.TOTP_KEY + " TYPE VARCHAR(32);");
             }
 
             if (!col.PLAYER_UUID.isEmpty() && isColumnMissing(md, col.PLAYER_UUID)) {
@@ -262,16 +262,6 @@ public class PostgreSqlDataSource extends AbstractSqlDataSource {
         }
     }
 
-    private boolean isColumnSizeIncorrect(DatabaseMetaData metaData, String columnName, int size) throws SQLException {
-        try (ResultSet rs = metaData.getColumns(null, null, tableName, columnName)) {
-            if (!rs.next()) {
-                throw new RuntimeException("Column " + columnName + " doesn't exist!");
-            }
-            int currentSize = rs.getInt("COLUMN_SIZE");
-            return size != currentSize;
-        }
-    }
-
     @Override
     public PlayerAuth getAuth(String user) {
         String sql = "SELECT * FROM " + tableName + " WHERE " + col.NAME + "=?;";
diff --git a/src/main/java/fr/xephi/authme/datasource/SQLite.java b/src/main/java/fr/xephi/authme/datasource/SQLite.java
index 08d6f7dbe..da1851bd3 100644
--- a/src/main/java/fr/xephi/authme/datasource/SQLite.java
+++ b/src/main/java/fr/xephi/authme/datasource/SQLite.java
@@ -184,9 +184,6 @@ public class SQLite extends AbstractSqlDataSource {
             if (isColumnMissing(md, col.TOTP_KEY)) {
                 st.executeUpdate("ALTER TABLE " + tableName
                     + " ADD COLUMN " + col.TOTP_KEY + " VARCHAR(32);");
-            } else if (isColumnSizeIncorrect(md, col.TOTP_KEY, 32)) {
-                st.executeUpdate("ALTER TABLE " + tableName
-                    + " ALTER COLUMN " + col.TOTP_KEY + " VARCHAR(32);");
             }
 
             if (!col.PLAYER_UUID.isEmpty() && isColumnMissing(md, col.PLAYER_UUID)) {
@@ -217,16 +214,6 @@ public class SQLite extends AbstractSqlDataSource {
         }
     }
 
-    private boolean isColumnSizeIncorrect(DatabaseMetaData metaData, String columnName, int size) throws SQLException {
-        try (ResultSet rs = metaData.getColumns(null, null, tableName, columnName)) {
-            if (!rs.next()) {
-                throw new RuntimeException("Column " + columnName + " doesn't exist!");
-            }
-            int currentSize = rs.getInt("COLUMN_SIZE");
-            return size != currentSize;
-        }
-    }
-
     @Override
     public void reload() {
         close(con);
diff --git a/src/main/java/fr/xephi/authme/datasource/SqLiteMigrater.java b/src/main/java/fr/xephi/authme/datasource/SqLiteMigrater.java
index b4a2a577b..a9da0dd91 100644
--- a/src/main/java/fr/xephi/authme/datasource/SqLiteMigrater.java
+++ b/src/main/java/fr/xephi/authme/datasource/SqLiteMigrater.java
@@ -46,7 +46,8 @@ class SqLiteMigrater {
      */
     static boolean isMigrationRequired(DatabaseMetaData metaData, String tableName, Columns col) throws SQLException {
         return SqlDataSourceUtils.isNotNullColumn(metaData, tableName, col.LAST_IP)
-            && SqlDataSourceUtils.getColumnDefaultValue(metaData, tableName, col.LAST_IP) == null;
+            && SqlDataSourceUtils.getColumnDefaultValue(metaData, tableName, col.LAST_IP) == null
+            && SqlDataSourceUtils.getColumnSize(metaData, tableName, col.TOTP_KEY) != 32;
     }
 
     /**
diff --git a/src/main/java/fr/xephi/authme/datasource/SqlDataSourceUtils.java b/src/main/java/fr/xephi/authme/datasource/SqlDataSourceUtils.java
index b115b276b..1a936f024 100644
--- a/src/main/java/fr/xephi/authme/datasource/SqlDataSourceUtils.java
+++ b/src/main/java/fr/xephi/authme/datasource/SqlDataSourceUtils.java
@@ -86,4 +86,24 @@ public final class SqlDataSourceUtils {
             return rs.getObject("COLUMN_DEF");
         }
     }
+
+    /**
+     * Returns the size of a column (as per its SQL definition).
+     *
+     * @param metaData the database meta data
+     * @param tableName the name of the table in which the column is
+     * @param columnName the name of the column to check
+     * @return the size of the column
+     * @throws SQLException :)
+     */
+    public static int getColumnSize(DatabaseMetaData metaData, String tableName,
+                                         String columnName) throws SQLException {
+        try (ResultSet rs = metaData.getColumns(null, null, tableName, columnName)) {
+            if (!rs.next()) {
+                throw new IllegalStateException("Did not find meta data for column '"
+                    + columnName + "' while checking its size");
+            }
+            return rs.getInt("COLUMN_SIZE");
+        }
+    }
 }