SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'deda9946c86bff3ac5490c79294da5963ce1117e5dbd6bf8c482795b0b95173c' 
  AND token = 'nVYC4h67yWINm7q/Oy1dXWT/Pzi1tUlbdrglet2xJQE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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