Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '50e7168e505b8d37ac61a314094f1cb6859f63e3b3d2b4c4e5171272cd492730' 
  AND token = 'DpciQxvrkGbhEO/3eg3LkTY4QFaIRCCd7LHpPlVpuS8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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