From BBC Scotland today:

The document says that firms, including garden centres and drive-through takeaways, can reopen in phase one, while construction, factories, warehouses, laboratories and small shops can resume work in the second phase. However, it does not give a comprehensive list of [356 550] individual businesses and which timelines they should follow.

From the Scottish Government in November 2019:

Number of Scottish businesses at record high.

A National Statistics Publication for Scotland.

The Businesses in Scotland 2019 report shows that, as of March 2019, there were an estimated 356,550 private sector businesses operating in Scotland – the highest number since current records began in 2000.

The statistics show that between March 2018 and March 2019, the estimated number of businesses increased by 2.8% (9,755 businesses).

That increase was driven by a 4.3% (7,270) rise in the number of unregistered businesses (those not registered for VAT and/or PAYE), which increased from 170,500 in March 2018 to 177,770 in March 2019.

The number of registered businesses also increased during that period – up by 2,485 businesses (1.4%) from 176,295 to 178,780 – also the highest since current records began.

In the same period there were 354,125 Small and Medium-sized Enterprises (SMEs) operating in Scotland, providing an estimated 1.2 million jobs. SMEs accounted for 99.3% of all private sector businesses, 55.4% of private sector employment, and 41.5% of private sector turnover.