SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77217b9b66a1b462d643e54379efacc34fa0950bc192850fe2c6d3591c255490' 
  AND token = 'NLqaoKr1BoRplHG7+X/By3rlS7sYHSF41n0/sauYW7Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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