SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '629b5e9afdba0a560cb681141c0de33a1c05c6153054518afa77f0378fc5d50b' 
  AND token = 'ym0TvX4z3YFPFwfzelDPsq4EjnxIcptjxzC/QIsbQYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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