String & Text Types0%

String & Text Types

Beginner12 min read•Updated: 2026-09-12

String & Text Types: CHAR, VARCHAR, TEXT, and BLOB

String data encompasses everything from customer names, emails, and postal codes to full-length blog posts, JSON strings, and product descriptions. MySQL provides several string and binary data types, each with distinct storage mechanics, indexing capabilities, and performance profiles.

1. `CHAR` vs `VARCHAR`: Fixed-Length vs Variable-Length

The two most frequently used string types are CHAR and VARCHAR.

 CHAR(5) storing "Hi":
 +---+---+---+---+---+
 | H | i |   |   |   |  <-- Always consumes 5 bytes (padded with spaces)!
 +---+---+---+---+---+
5 
 VARCHAR(5) storing "Hi":
 +-------+---+---+
 | len=2 | H | i |      <-- Consumes 1 length byte + 2 data bytes = 3 bytes!
 +-------+---+---+

Feature	`CHAR(M)`	`VARCHAR(M)`
Length Type	Fixed length (always allocates `M` characters).	Variable length (allocates only actual characters + length prefix).
Max Capacity	0 to 255 characters.	0 to 65,535 bytes (shared across the entire row).
Padding	Right-padded with spaces upon storage; stripped on retrieval.	No trailing padding.
Length Prefix	None (0 bytes).	1 byte (if length <= 255), 2 bytes (if length > 255).
Ideal For	Fixed-length codes: Country code (`IN`, `US`), MD5/SHA256 hashes, PIN codes.	Variable-length strings: Names, email addresses, street addresses.

2. Large Text Types: `TEXT` Family

When a string exceeds the capacity of VARCHAR or represents large prose (e.g., article content, product reviews), use the TEXT family:

Type	Maximum Storage	Typical Use Case
`TINYTEXT`	255 bytes	Short notes, subtitles.
`TEXT`	65,535 bytes (~64 KB)	Blog comments, product descriptions.
`MEDIUMTEXT`	16,777,215 bytes (~16 MB)	Full articles, book chapters, long HTML pages.
`LONGTEXT`	4,294,967,295 bytes (~4 GB)	Massive legal contracts, raw log dumps.

Note

[!NOTE] TEXT columns cannot have default values in older MySQL versions and cannot be fully indexed in their entirety without specifying a prefix length (e.g., INDEX (content(255))).

3. Binary Data: `BINARY`, `VARBINARY`, and `BLOB`

While CHAR and VARCHAR store text (subject to character sets and collations), binary types store raw byte sequences:

VARBINARY(M): Variable-length byte string (e.g., encrypted hashes, UUID binary blobs).
BLOB (Binary Large Object): Stores raw binary data such as PDF documents, images, or audio clips. Divided into TINYBLOB, BLOB, MEDIUMBLOB, and LONGBLOB.

1CREATE TABLE user_profiles (
  user_id INT PRIMARY KEY AUTO_INCREMENT,
  country_code CHAR(2) NOT NULL, -- Fixed 2 characters (e.g. 'IN', 'US')
  full_name VARCHAR(100) NOT NULL, -- Variable up to 100 characters
  email VARCHAR(255) NOT NULL UNIQUE,
  bio TEXT, -- Markdown biography
  profile_photo_blob MEDIUMBLOB -- Raw JPEG bytes (Max 16MB)
8);

4. Best Practices & Common Pitfalls

Avoid Storing Images Directly as BLOBs: Storing large image files directly inside database tables bloats the database backup size and slows down caching. Best practice: Store files on AWS S3, Cloudflare R2, or a disk directory, and store only the URL string (VARCHAR(500)) in the database!
Beware of the 65,535 Row Size Limit: In MySQL, the maximum row size for all columns combined is 65,535 bytes. Large TEXT and BLOB columns store only a 24-byte pointer on-page, with the rest stored in off-page overflow tablespaces.

Interactive Quiz• Knowledge Check

Multiple Choice Questions

Question 1

Which data type is most efficient for storing fixed-length two-character country codes (e.g., 'IN', 'US', 'UK')?

Question 2

How does VARCHAR(100) store a string containing 10 characters?

Question 3

What is the maximum storage capacity of a standard LONGTEXT column in MySQL?

Question 4

What is the fundamental difference between VARCHAR and VARBINARY?

Question 5

Why is it considered an architectural anti-pattern to store high-resolution images as MEDIUMBLOB directly in a relational table?

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Date & Time Types

String & Text Types

Beginner12 min read•Updated: 2026-09-12

Study Materials Cheatsheet

String & Text Types: CHAR, VARCHAR, TEXT, and BLOB

1. `CHAR` vs `VARCHAR`: Fixed-Length vs Variable-Length

The two most frequently used string types are CHAR and VARCHAR.

 CHAR(5) storing "Hi":
 +---+---+---+---+---+
 | H | i |   |   |   |  <-- Always consumes 5 bytes (padded with spaces)!
 +---+---+---+---+---+
5 
 VARCHAR(5) storing "Hi":
 +-------+---+---+
 | len=2 | H | i |      <-- Consumes 1 length byte + 2 data bytes = 3 bytes!
 +-------+---+---+

Feature	`CHAR(M)`	`VARCHAR(M)`
Length Type	Fixed length (always allocates `M` characters).	Variable length (allocates only actual characters + length prefix).
Max Capacity	0 to 255 characters.	0 to 65,535 bytes (shared across the entire row).
Padding	Right-padded with spaces upon storage; stripped on retrieval.	No trailing padding.
Length Prefix	None (0 bytes).	1 byte (if length <= 255), 2 bytes (if length > 255).
Ideal For	Fixed-length codes: Country code (`IN`, `US`), MD5/SHA256 hashes, PIN codes.	Variable-length strings: Names, email addresses, street addresses.

2. Large Text Types: `TEXT` Family

When a string exceeds the capacity of VARCHAR or represents large prose (e.g., article content, product reviews), use the TEXT family:

Type	Maximum Storage	Typical Use Case
`TINYTEXT`	255 bytes	Short notes, subtitles.
`TEXT`	65,535 bytes (~64 KB)	Blog comments, product descriptions.
`MEDIUMTEXT`	16,777,215 bytes (~16 MB)	Full articles, book chapters, long HTML pages.
`LONGTEXT`	4,294,967,295 bytes (~4 GB)	Massive legal contracts, raw log dumps.

Note

[!NOTE] TEXT columns cannot have default values in older MySQL versions and cannot be fully indexed in their entirety without specifying a prefix length (e.g., INDEX (content(255))).

3. Binary Data: `BINARY`, `VARBINARY`, and `BLOB`

While CHAR and VARCHAR store text (subject to character sets and collations), binary types store raw byte sequences:

VARBINARY(M): Variable-length byte string (e.g., encrypted hashes, UUID binary blobs).
BLOB (Binary Large Object): Stores raw binary data such as PDF documents, images, or audio clips. Divided into TINYBLOB, BLOB, MEDIUMBLOB, and LONGBLOB.

1CREATE TABLE user_profiles (
  user_id INT PRIMARY KEY AUTO_INCREMENT,
  country_code CHAR(2) NOT NULL, -- Fixed 2 characters (e.g. 'IN', 'US')
  full_name VARCHAR(100) NOT NULL, -- Variable up to 100 characters
  email VARCHAR(255) NOT NULL UNIQUE,
  bio TEXT, -- Markdown biography
  profile_photo_blob MEDIUMBLOB -- Raw JPEG bytes (Max 16MB)
8);

4. Best Practices & Common Pitfalls

Avoid Storing Images Directly as BLOBs: Storing large image files directly inside database tables bloats the database backup size and slows down caching. Best practice: Store files on AWS S3, Cloudflare R2, or a disk directory, and store only the URL string (VARCHAR(500)) in the database!
Beware of the 65,535 Row Size Limit: In MySQL, the maximum row size for all columns combined is 65,535 bytes. Large TEXT and BLOB columns store only a 24-byte pointer on-page, with the rest stored in off-page overflow tablespaces.

Interactive Quiz• Knowledge Check

Multiple Choice Questions

Question 1

Which data type is most efficient for storing fixed-length two-character country codes (e.g., 'IN', 'US', 'UK')?

Question 2

How does VARCHAR(100) store a string containing 10 characters?

Question 3

What is the maximum storage capacity of a standard LONGTEXT column in MySQL?

Question 4

What is the fundamental difference between VARCHAR and VARBINARY?

Question 5

Why is it considered an architectural anti-pattern to store high-resolution images as MEDIUMBLOB directly in a relational table?

Next Lesson

Date & Time Types

Continue learning with hands-on practice, examples, and exercises in the upcoming topic.

Related Lessons

Previous Lesson	Next Lesson
Numeric Data Types	Date & Time Types

Practice Quiz

Test your understanding of this lesson with 5 questions. Each question has one correct answer.

Previous Next

String & Text Types: CHAR, VARCHAR, TEXT, and BLOB

1. CHAR vs VARCHAR: Fixed-Length vs Variable-Length

2. Large Text Types: TEXT Family

3. Binary Data: BINARY, VARBINARY, and BLOB

4. Best Practices & Common Pitfalls

Multiple Choice Questions

Date & Time Types

Related Lessons

Practice Quiz

Loading Page Content...

String & Text Types: CHAR, VARCHAR, TEXT, and BLOB

1. CHAR vs VARCHAR: Fixed-Length vs Variable-Length

2. Large Text Types: TEXT Family

3. Binary Data: BINARY, VARBINARY, and BLOB

4. Best Practices & Common Pitfalls

Multiple Choice Questions

Date & Time Types

Related Lessons

Practice Quiz

1. `CHAR` vs `VARCHAR`: Fixed-Length vs Variable-Length

2. Large Text Types: `TEXT` Family

3. Binary Data: `BINARY`, `VARBINARY`, and `BLOB`

1. `CHAR` vs `VARCHAR`: Fixed-Length vs Variable-Length

2. Large Text Types: `TEXT` Family

3. Binary Data: `BINARY`, `VARBINARY`, and `BLOB`