SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'afcfc408b2024f40094b7e466af39a0fc43f96a653678072da1933869cf02ae7' 
  AND token = 'AdfiIEl8dV9qfsFvBGOjh617ZsRvO/x4rA+8O6YcNcs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}