SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4210d9764afe451eeb54a5f47aa6aef09a5f798ce5673e9793fb5a6e6c83aa1a' 
  AND token = 'rwQKHfLWJg+DEvINcVltprz/uf7/aZhY6ZHAZ4wUbR4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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