SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7edec4a854f536183ffd005bbd336c6f1937b445c7a340c4ede361977e89ab54' 
  AND token = '4PcaydGm3Gj2vhfdKMjIn78ZYOB/R8PcnCLuClugW5w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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