SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0eadd195cbd9018c048591e14da4220074b91e8a337a31287a56784db90799c7' 
  AND token = 'bcP+J8FN8THxPv4hnAI1dE9npCP5DYRKkfqwC7KDL8w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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