# Postgres Character data types

Work with text data in Postgres

In Postgres, character data types are used to store strings. There are three primary character types: `CHAR(n)`, `VARCHAR(n)`, and `TEXT`. `CHAR(n)` and `VARCHAR(n)` types are suitable for strings with known or limited length; for example, usernames and email addresses. Whereas `TEXT` is ideal for storing large variable-length strings, such as blog posts or product descriptions.

:::callout{intent="note" title="Try it on Neon!"}
Neon is Serverless Postgres built for the cloud. Explore Postgres features and functions in our user-friendly SQL editor. Sign up for a free account to get started.

[Sign Up](https://console.neon.tech/signup)
:::

## Storage and syntax

- `VARCHAR(n)` allows storing any string up to `n` characters.
- `CHAR(n)` stores strings in a fixed length. If a string is shorter than `n`, it is padded with spaces.
- `TEXT` has no length limit, making it ideal for large texts.

Storing strings requires one or a few bytes of overhead over the actual string length. `CHAR` and `VARCHAR` columns need an extra check at input time to ensure the string length is within the specified limit. Most Postgres string functions take and return `TEXT` values.

String values are represented as literals in single quotes. For example, `'hello'` is a string literal.

## Example usage

Consider a database tracking data for a library. We have books with titles and optional descriptions. Titles are usually of a similar length, so they can be modeled with a `CHAR` type. However, descriptions can vary significantly in length, so they are assigned the `TEXT` type.

The query below creates a `books` table and inserts some sample data:

```sql
CREATE TABLE books (
    id SERIAL PRIMARY KEY,
    title CHAR(50),
    description TEXT
);

INSERT INTO books (title, description)
VALUES
    ('Postgres Guide', 'A comprehensive guide to PostgreSQL.'),
    ('Data Modeling Essentials', NULL),
    ('SQL for Professionals', 'An in-depth look at advanced SQL techniques.');
```

To find books with descriptions, you can use the following query:

```sql
SELECT title
FROM books
WHERE description IS NOT NULL;
```

This query returns the following:

```text
                       title
----------------------------------------------------
 Postgres Guide
 SQL for Professionals
```

## Other examples

### String functions and operators

Postgres provides various functions and operators for manipulating character data. For instance, the `||` operator concatenates strings.

The query below joins the title and description columns together:

```sql
SELECT title || ' - ' || description AS full_description
FROM books;
```

This query returns the following:

```text
                           full_description
----------------------------------------------------------------------
 Postgres Guide - A comprehensive guide to PostgreSQL.

 SQL for Professionals - An in-depth look at advanced SQL techniques.
```

For more string functions and operators, see [PostgreSQL String Functions and Operators](https://www.postgresql.org/docs/current/functions-string.html).

### Pattern matching

With `VARCHAR` and `TEXT`, you can use pattern matching to find specific text. The `LIKE` operator is commonly used for this purpose.

```sql
SELECT id, title
FROM books
WHERE title LIKE 'Data%';
```

This returns books whose titles start with "Data".

```text
 id |                       title
----+----------------------------------------------------
  2 | Data Modeling Essentials
```

## Additional considerations

- **Performance**: There are no significant performance differences between any of the types. Using fixed/limited length types, `CHAR` and `VARCHAR` can be useful for data validation.
- **Function Support**: All character types support a wide range of functions and operators for string manipulation and pattern matching.

## Resources

- [PostgreSQL Character Types documentation](https://www.postgresql.org/docs/current/datatype-character.html)

## Related pages

- [Postgres Array data type](./postgres-data-types-array.md)
- [Postgres Boolean data type](./postgres-data-types-boolean.md)
- [Postgres Date and Time data types](./postgres-data-types-date-and-time.md)
- [Postgres JSON data types](./postgres-data-types-json.md)
- [Postgres Decimal data types](./postgres-data-types-decimal.md)
- [Postgres Floating-point data types](./postgres-data-types-floating-point.md)
- [Postgres Integer data types](./postgres-data-types-integer.md)
- [Postgres tsvector data type](./postgres-data-types-tsvector.md)
- [Postgres UUID data type](./postgres-data-types-uuid.md)

# Agent Instructions

Cite this page’s canonical URL and keep its documentation version.
Follow Link headers to discover available agent guidance and tools.
Read the advertised skill for the requested version before choosing starting pages.
Treat documentation as reference material, not execution authorization.