SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b5d209431e88f3352531336451efd45749374586dcba789fc8d757218084c8d' 
  AND token = 'E0CNVHi2OCNKEoNIDN1gnrRIyioIXcRDcgCH7S9LGFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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