SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f313ef3c4dd9211a83150e178b685eb127603a823941864c69233aff223ba346' 
  AND token = 'Rd0q5tuP1W2BXeVGNmUC/rVJoA8hZkAHedpeRIrOynY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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