SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9023a0f09bcf7083fe7842a481c61920e1e5c72e33b2980d7acbfba4a8e6bbae' 
  AND token = 'b/YULBVDRUQ4WjJ3d77B2LULICp27i1L5FBL4uM0SbQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}