diff --git a/README.md b/README.md
index bd07068..5fcb997 100644
--- a/README.md
+++ b/README.md
@@ -720,3 +720,7 @@ The following guidelines indicate when the use of an index should be reconsidere
     DROP INDEX index_name;
 
 # SQL - ALTER TABLE  ✍
+
+- The SQL ALTER TABLE command is used to add, delete or modify columns in an existing table. 
+- You should also use the ALTER TABLE command to add and drop various constraints on an existing table.
+