Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ec5ce4374c3ce68f6c01226cc4d9a1e8e5371e02c69852ccc582dfa4fe81f6b1' 
  AND token = 'WC6HseqPrNqyp5F3SWcVBPm05h8mstH+UGDFuGVOLrE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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