SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69ae58e45cd59dfa163aff451b8de22520ab578c7e513308951da56959ecf324' 
  AND token = 'YPJ6fpr8qH+JRz/nsBqwB4Gl3gSaoY2axHqtwf5tC6Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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