SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f8d2c338dae9b0b33ea0eea899207bb9251a083fd874633f2bed565488e2418' 
  AND token = 'u9/C5tNDAb8Ml3DDeoIsJcOKKKO4bEQ4fgFzk6vHoxI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}