SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '84483604a88985f4ff890d35a1044df4b67c50115bdab457ab838e357070649f' 
  AND token = 'bzhvVjdUCT8+Q/Udn8pLvpsq8ac+ygMFKw6p1CDsfqs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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