SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e06db344c20e1c25f37df538f844fcfbca6da2f12ebfe02c3d0c8b3c2785619a' 
  AND token = 'MXF3KbwC4Nxw+PIRzz5EGFQjZfNR5v+l9HKFTjQwGsI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

JSON explain

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