@@ -354,12 +354,14 @@ sql.exec();
 ### If not or If exists
 
 ```javascript
-instance.ifnot('user', function(instance, response) {
+instance.ifnot('user', function(error, response) {
+    // error === ErrorBuilder
     // It will be executed when the results won't be contain `user` property
     // Is executed in order
 });
 
-instance.ifexists('user', function(instance, response) {
+instance.ifexists('user', function(error, response) {
+    // error === ErrorBuilder
     // It will be executed when the results will contain `user` property
     // Is executed in order
 });
@@ -428,6 +430,7 @@ select.limit(1);
 
 // IMPORTANT:
 sql.prepare(function(error, response, resume) {
+    // error === ErrorBuilder
     sql.builder('address').set('idaddress', response.address.id);
     resume();
 });
@@ -456,6 +459,8 @@ select.limit(1);
 // IMPORTANT:
 sql.validate(function(error, response, resume) {
 
+    // error === ErrorBuilder
+
     if (!response.address) {
         error.push('Sorry, address not found');
         // cancel pending queries
@@ -517,6 +522,7 @@ sql.skip(); // skip orders
 sql.select('orders', 'tbl_orders');
 
 sql.bookmark(function(error, response) {
+    // error === ErrorBuilder
     // skip logs
     sql.skip('logs');
 });
@@ -536,6 +542,7 @@ Bookmark is same as `sql.prepare()` function but without `resume` argument.
 sql.select('users', 'tbl_users');
 
 sql.bookmark(function(error, response) {
+    // error === ErrorBuilder
     console.log(response);
     response['custom'] = 'Peter';
 });
@@ -556,6 +563,8 @@ sql.select('users', 'tbl_users');
 
 sql.validate(function(error, response, resume) {
 
+    // error === ErrorBuilder
+
     if (!response.users || respone.users.length === 0)
         error.push(new Error('This is error'));