You are viewing the archived documentation of TiDB, which no longer receives updates. View the latest LTS version docs ↗

Encryption and Compression Functions

TiDB supports most of the encryption and compression functions available in MySQL 8.0.

Supported functions

Name	Description
`MD5()`	Calculate MD5 checksum
`PASSWORD()`	Calculate and return a password string
`RANDOM_BYTES()`	Return a random byte vector
`SHA1(), SHA()`	Calculate an SHA-1 160-bit checksum
`SHA2()`	Calculate an SHA-2 checksum
`SM3()`	Calculate an SM3 checksum (currently MySQL does not support this function)
`AES_DECRYPT()`	Decrypt using AES
`AES_ENCRYPT()`	Encrypt using AES
`COMPRESS()`	Return result as a binary string
`UNCOMPRESS()`	Uncompress a string compressed
`UNCOMPRESSED_LENGTH()`	Return the length of a string before compression
`VALIDATE_PASSWORD_STRENGTH()`	Validate the password strength

The block_encryption_mode variable sets the encryption mode that is used for AES_ENCRYPT() and AES_DECRYPT().

The validate_password.* variables affect the VALIDATE_PASSWORD_STRENGTH() function.

DES_DECRYPT(), DES_ENCRYPT(), OLD_PASSWORD(), ENCRYPT(): these functions were deprecated in MySQL 5.7 and removed in 8.0.
Functions only available in MySQL Enterprise Issue #2632.

TiDB does not support the STATEMENT_DIGEST() and STATEMENT_DIGEST_TEXT() functions.