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SQL CREATE TABLE Statement
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SQL CREATE TABLE Statement
Learn how to use CREATE TABLE to define a database schema and structure your data efficiently.
What Is the SQL CREATE TABLE Statement?
The CREATE TABLE statement is used to define a new table in a database. It lets you specify column names, data types, and constraints like primary keys or NOT NULL requirements.
Basic Syntax
CREATE TABLE table_name (
column1 datatype constraint,
column2 datatype constraint,
...
);Practical CREATE TABLE Example
Here's how you might define a simple Users table in the TokTuk dataset:
CREATE TABLE Users (
user_id INTEGER PRIMARY KEY,
username TEXT NOT NULL,
email TEXT UNIQUE NOT NULL,
created_at DATE DEFAULT CURRENT_DATE
);Using Constraints
- PRIMARY KEY – Uniquely identifies each row.
- NOT NULL – Prevents null values in a column.
- UNIQUE – Ensures all values in a column are distinct.
- DEFAULT – Assigns a default value if none is provided.
More Examples
Videos Table
CREATE TABLE Videos (
video_id INTEGER PRIMARY KEY,
title TEXT NOT NULL,
upload_date DATE,
views INTEGER DEFAULT 0
);Interactions Table
CREATE TABLE Interactions (
interaction_id INTEGER PRIMARY KEY,
user_id INTEGER NOT NULL,
video_id INTEGER NOT NULL,
interaction_type TEXT,
timestamp DATETIME DEFAULT CURRENT_TIMESTAMP
);Pro Tips for CREATE TABLE
- Use clear, descriptive column names.
- Define appropriate data types for each column.
- Always set a primary key — it's your table's unique fingerprint.
- Use
NOT NULLto prevent incomplete data. - Use
DEFAULTvalues to avoid repetitive inserts.