Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '844e9432a3dd052ccddd0f5261135045d315b9b4d129e58c437301c62554a279' 
  AND token = 'Y4RQp1n5+KlfPftXhZyi7gQEbiM/vYHTccmsGTmSnAc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00009

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}