From 79a656e1718fbae5b435d16eefb3a207b78a1fdd Mon Sep 17 00:00:00 2001
From: Akash Sharma <35839624+Adaverse@users.noreply.github.com>
Date: Tue, 12 Sep 2023 20:57:19 +0530
Subject: [PATCH] Fixing `PRIMARY_KEY` `NULL` constraint (#4465)

---
 .../roadmaps/sql/content/105-data-constraints/102-unique.md   | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/data/roadmaps/sql/content/105-data-constraints/102-unique.md b/src/data/roadmaps/sql/content/105-data-constraints/102-unique.md
index 74db5f63e..0d0c0cf97 100644
--- a/src/data/roadmaps/sql/content/105-data-constraints/102-unique.md
+++ b/src/data/roadmaps/sql/content/105-data-constraints/102-unique.md
@@ -2,7 +2,7 @@
 
 The `UNIQUE` constraint ensures that all values in a column are different; that is, each value in the column should occur only once.
 
-Both the `UNIQUE` and `PRIMARY KEY` constraints provide a guarantee for uniqueness for a column or set of columns. However, a primary key can contain only `NULL`, and each table can have only one primary key. On the other hand, a `UNIQUE` constraint allows for one `NULL` value, and a table can have multiple `UNIQUE` constraints.
+Both the `UNIQUE` and `PRIMARY KEY` constraints provide a guarantee for uniqueness for a column or set of columns. However, a primary key cannot contain `NULL` since it uniquely identifies each row, and each table can have only one primary key. On the other hand, a `UNIQUE` constraint allows for one `NULL` value, and a table can have multiple `UNIQUE` constraints.
 
 ## Syntax
 ```sql
@@ -51,4 +51,4 @@ ALTER TABLE table_name
 DROP CONSTRAINT constraint_name;
 ```
 
-Here, `constraint_name` is the name of the `UNIQUE` constraint that you want to drop.
\ No newline at end of file
+Here, `constraint_name` is the name of the `UNIQUE` constraint that you want to drop.