From 3868bc7c791e3342e2f431af386ccdc3908dc600 Mon Sep 17 00:00:00 2001
From: GowthamRaj K <43011442+gowthamrajk@users.noreply.github.com>
Date: Thu, 29 Jul 2021 08:24:26 +0530
Subject: [PATCH] Update README.md

---
 README.md | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/README.md b/README.md
index 9b5401b..5de7755 100644
--- a/README.md
+++ b/README.md
@@ -678,6 +678,16 @@ There are different types of joins available in SQL −
 - Simply put, an index is a pointer to data in a table. 
 - An index in a database is very similar to an index in the back of a book.
 
+The following guidelines indicate when the use of an index should be reconsidered.
+
+**- Indexes should not be used on small tables.
+
+Tables that have frequent, large batch updates or insert operations.
+
+Indexes should not be used on columns that contain a high number of NULL values.
+
+Columns that are frequently manipulated should not be indexed.
+
 ### CREATE INDEX
 
     CREATE INDEX index_name ON table_name;