remove Default Constraint and handle old shop

Former-commit-id: 150fdc5

Author: sandtechnology

src/main/java/org/maxgamer/quickshop/database/DatabaseHelper.java

@@ -114,10 +114,10 @@ private void checkColumns() {
             // Reremake - DataStorage @TODO needs testing
             if (plugin.getDatabase().getCore() instanceof MySQLCore) {
                 ps = db.getConnection().prepareStatement("ALTER TABLE " + plugin
-                        .getDbPrefix() + "shops ADD extra LONGTEXT NOT NULL DEFAULT '{}'");
+                        .getDbPrefix() + "shops ADD extra LONGTEXT NOT NULL");
             } else {
                 ps = db.getConnection().prepareStatement("ALTER TABLE " + plugin
-                        .getDbPrefix() + "shops ADD COLUMN extra TEXT NOT NULL DEFAULT '{}'");
+                        .getDbPrefix() + "shops ADD COLUMN extra TEXT NOT NULL");
             }
             Util.debugLog("Setting up the column EXTRA...");
             ps.execute();

src/main/java/org/maxgamer/quickshop/shop/ShopLoader.java

@@ -425,6 +425,10 @@ public class ShopDatabaseInfoOrigin {
                 this.type = rs.getInt("type");
                 this.unlimited = rs.getBoolean("unlimited");
                 this.extra = rs.getString("extra");
+                //handle old shops
+                if (extra == null) {
+                    extra = "{}";
+                }
             } catch (SQLException sqlex) {
                 exceptionHandler(sqlex, null);
             }