SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c594334bd6914842e750e88870671232f43de7819a485cdcad5b9557753c6949' 
  AND token = 'X3IN4QqPMRToUKZur55dEOcfetxgZkj7ah/wI8dcweA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables