sqlite
  1. sqlite-data-types
PreviousNext

SQLite Data Types

SQLite supports a range of data types for storing data in tables. Understanding the data types supported by SQLite and how to use them can help improve the performance and optimization of your database.

Syntax

In SQLite, you can create a table with the following syntax:

CREATE TABLE tablename (
  column1 datatype [constraints],
  column2 datatype [constraints],
  ...
);

Here, the datatype of the column specifies the type of data that can be stored in that column.

Example

Suppose we want to create a table to store information about products, with columns for the product name, category, and price. We can create the table with the following syntax:

CREATE TABLE products (
  product_id INTEGER PRIMARY KEY,
  product_name TEXT NOT NULL,
  category TEXT,
  price REAL DEFAULT 0.0
);

Output

The above statement creates a table called products with columns named product_id, product_name, category, and price. The product_id column is specified as the primary key for the table, and the product_name column is specified as NOT NULL. The price column has a default value of 0.0.

Explanation

In the example above, we use INTEGER, TEXT, and REAL data types to define the columns of the products table. The INTEGER data type is used to store integer values, TEXT is used to store text values, and REAL is used to store floating-point values.

We specify the product_id column as the primary key for the table, which is a unique identifier for each row. The product_name column is specified as NOT NULL, which means that it cannot be empty.

The price column has a default value of 0.0, which means that if a value is not specified for the column it will default to 0.0.

Use

SQLite data types can be used to optimize the performance and storage of your database. By choosing the appropriate data type for each column, you can reduce the amount of space required to store data and improve the search and retrieval of that data.

Important Points

  • Choose the appropriate data type for each column based on the type of data that it will store. This can help optimize storage and search performance.
  • Use constraints such as NOT NULL and DEFAULT to enforce data integrity and provide default values for columns.
  • SQLite supports a range of data types, including integer, text, real, blob, and null.
  • You can use the CAST function to convert data between data types.
  • Be aware of the limitations of certain data types, such as storing very large or precise numbers.

Summary

In this tutorial, we learned about the data types supported by SQLite and how to use them to define columns in a table. We saw an example of creating a table to store information about products and specifying constraints such as NOT NULL and DEFAULT. It's important to choose the appropriate data type for each column to optimize storage and search performance and enforce data integrity.

SyntaxOperators
Published on: