diff --git a/forward_engineering/api.js b/forward_engineering/api.js
index e6fd1a0..818fd12 100644
--- a/forward_engineering/api.js
+++ b/forward_engineering/api.js
@@ -1,8 +1,7 @@
 const reApi = require('../reverse_engineering/api');
 const { createLogger } = require('../reverse_engineering/helpers/loggerHelper');
 const applyToInstanceHelper = require('./applyToInstanceHelper');
-const { commentDropStatements } = require('./helpers/commentDropStatements');
-const { DROP_STATEMENTS } = require('./helpers/constants');
+const { commentDropStatements, doesScriptContainDropStatements} = require('./helpers/commentDropStatements');
 
 module.exports = {
 	generateScript(data, logger, callback, app) {
@@ -105,7 +104,7 @@ module.exports = {
 			const cb = (error, script = '') =>
 				callback(
 					error,
-					DROP_STATEMENTS.some(statement => script.includes(statement)),
+					doesScriptContainDropStatements(script),
 				);
 
 			if (data.level === 'container') {
diff --git a/forward_engineering/helpers/commentDropStatements.js b/forward_engineering/helpers/commentDropStatements.js
index 2c0c109..e37e97d 100644
--- a/forward_engineering/helpers/commentDropStatements.js
+++ b/forward_engineering/helpers/commentDropStatements.js
@@ -1,17 +1,50 @@
 const { DROP_STATEMENTS } = require('./constants');
 
+const isDropNotNullStatementRegex = /ALTER TABLE IF EXISTS .+ ALTER COLUMN .+ DROP NOT NULL;/;
+
+const isDropConstraintStatementRegex = /ALTER TABLE IF EXISTS .+ DROP CONSTRAINT IF EXISTS .+;/;
+
+const dropCommentRegex = /COMMENT ON (TABLE|SCHEMA|VIEW|COLUMN) .+ IS NULL;/;
+
+/**
+ * @param scriptLine {string}
+ * @return {boolean}
+ * */
+const shouldStatementBeCommentedOut = (scriptLine) => {
+	const doesContainDropStatements = DROP_STATEMENTS.some(statement => scriptLine.includes(statement));
+	if (doesContainDropStatements) {
+		return true;
+	}
+
+	return [
+		isDropNotNullStatementRegex,
+		isDropConstraintStatementRegex,
+		dropCommentRegex,
+	].some(regex => regex.test(scriptLine));
+}
+
+/**
+ * @param script {string}
+ * @return {boolean}
+ * */
+const doesScriptContainDropStatements = (script) => {
+	return script.split('\n')
+		.some(shouldStatementBeCommentedOut);
+}
+
+
 const commentDropStatements = (script = '') =>
 	script
 		.split('\n')
 		.map(line => {
-			if (DROP_STATEMENTS.some(statement => line.includes(statement))) {
+			if (shouldStatementBeCommentedOut(line)) {
 				return `-- ${line}`;
-			} else {
-				return line;
 			}
+			return line;
 		})
 		.join('\n');
 
 module.exports = {
 	commentDropStatements,
+	doesScriptContainDropStatements,
 };