Upserting rows

It is possible to perform 'upserts' by taking advantage of the 'overwrite' strategy.

Currently, there are three concurrency strategies:

• optimistic Raises an exception if another row was already inserted on that primary key.
• overwrite Overwrites the property, regardless of changes by others.
• skipOnConflict Silently avoids updating the property if another user has modified it in the interim.

The concurrency option can be set either for the whole table or individually for each column. In the example below, we've set the concurrency strategy on vendor table to overwrite except for the column balance+ which uses theskipOnConflict` strategy.

In this particular case, a row with id: 1 already exists, the name and isActive fields will be overwritten, but the balance will remain the same as in the original record, demonstrating the effectiveness of combining multiple concurrency strategies.

import map from './map';
const db = map.sqlite('demo.db');

insertRows();

async function insertRows() {

  db2 = db({
    vendor: {
      balance: {
        concurrency: 'skipOnConflict'
      },
      concurrency: 'overwrite'
    }
  });

  await db2.vendor.insert({
    id: 1,
    name: 'John',
    balance: 100,
    isActive: true
  });

  //this will overwrite all fields but balance
  const george = await db2.vendor.insert({
    id: 1,
    name: 'George',
    balance: 177,
        isActive: false
  });
  console.dir(george, {depth: Infinity});
  // {
  //   id: 1,
  //   name: 'George',
  //   balance: 100,
  //   isActive: false
  // }
}