SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf9ec497b1646197ca2aac9171e341dadd68d4416e1ac422e9897039bf1bd6cb' 
  AND token = 'hXQk82xhnB2HvERz4PsKkRI6VyvzB8j7A0zBtRCOhAk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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