Syntax\n------\n\nUNCOMPRESS(string_to_uncompress)\n\nDescription\n-----------\n\nUncompresses a string compressed by the COMPRESS() function. If the argument is not a compressed value, the result is NULL. This function requires MariaDB to have been compiled with a compression library such as zlib. Otherwise, the return value is always NULL. The have_compress server system variable indicates whether a compression library is present.\n\nExamples\n--------\n\nSELECT UNCOMPRESS(COMPRESS('a string'));\n+----------------------------------+\n| UNCOMPRESS(COMPRESS('a string')) |\n+----------------------------------+\n| a string                         |\n+----------------------------------+\n\nSELECT UNCOMPRESS('a string');\n+------------------------+\n| UNCOMPRESS('a string') |\n+------------------------+\n| NULL                   |\n+------------------------+\n\nURL: https://mariadb.com/docs/server/reference/sql-functions/secondary-functions/encryption-hashing-and-compression-functions/uncompress