INSERT INTO – How to Add Data into a Table in SQL

🔧 Quick Syntax:

INSERT INTO table_name (column1, column2, ...)
VALUES (value1, value2, ...);

This is how you tell SQL:
“Yo, here’s the table. I’m giving you these values. Save them like this.”

🧾 Let’s say you have a table called friends

It has the following structure:

Column	Data Type	Notes
id	INT	Auto-increment, Primary Key
name	VARCHAR(50)	Required
age	INT	Optional
phone	VARCHAR(15)	Optional

✅ Adding One Friend

INSERT INTO friends (name, age, phone)
VALUES ('Ravi', 25, '9876543210');

💡 Output:

Query OK, 1 row affected

The data has been added to your table. SQL automatically gives id = 1 since it’s set to auto-increment.

➕ Adding Another Friend

INSERT INTO friends (name, age, phone)
VALUES ('Simran', 28, '9123456789');

💡 Output:

Query OK, 1 row affected

Table Now Looks Like:

id	name	age	phone
1	Ravi	25	9876543210
2	Simran	28	9123456789

❌ What Happens If You Miss a Required Column?

INSERT INTO friends (age, phone)
VALUES (30, '9999999999');

⚠️ Output:

ERROR 1364 (HY000): Field 'name' doesn't have a default value

Why? The name column was marked NOT NULL, so SQL won’t allow it to be empty.

📦 Adding Multiple Friends at Once

INSERT INTO friends (name, age, phone)
VALUES 
  ('Aman', 22, '8888888888'),
  ('Neha', 26, '7777777777'),
  ('Karan', 24, '6666666666');

💡 Output:

Query OK, 3 rows affected

Updated Table:

id	name	age	phone
1	Ravi	25	9876543210
2	Simran	28	9123456789
3	Aman	22	8888888888
4	Neha	26	7777777777
5	Karan	24	6666666666

💤 What If You Don’t Know All Values?

INSERT INTO friends (name, age)
VALUES ('Karan', 24);

SQL will fill the missing phone column with NULL, since it’s optional.

🧃 Recap

• INSERT INTO lets you add real data into your table
• Always include required columns like NOT NULL ones
• Use one row at a time or many rows in one go
• AUTO_INCREMENT handles IDs — you don’t have to set them manually