Utility #

A collection of utilities that the knex library provides for convenience.

batchInsert #

knex.batchInsert(tableName)

The batchInsert utility will insert a batch of rows wrapped inside a transaction (which is automatically created unless explicitly given a transaction using transacting), at a given chunkSize.

It's primarily designed to be used when you have thousands of rows to insert into a table.

By default, the chunkSize is set to 1000.

BatchInsert also allows for returning values and supplying transactions using transacting.

const rows = [{/*...*/}, {/*...*/}];
const chunkSize = 30;
knex.batchInsert('TableName', rows, chunkSize)
  .returning('id')
  .then(function(ids) { /*...*/ })
  .catch(function(error) { /*...*/ });

knex.transaction(function(tr) {
  return knex.batchInsert('TableName', rows, chunkSize)
    .transacting(tr)
  })
  .then(function() { /*...*/ })
  .catch(function(error) { /*...*/ });

now #

knex.fn.now(precision)

Return the current timestamp with a precision (optional)

table.datetime('some_time', { precision: 6 }).defaultTo(knex.fn.now(6))

uuid #

knex.fn.uuid()

Return a uuid generation function. Not supported by Redshift

table.uuid('uuid').defaultTo(knex.fn.uuid())

uuidToBin #

knex.fn.uuidToBin(uuid)

Convert a string uuid (char(36)) to a binary uuid (binary(16))

knex.schema.createTable('uuid_table', (t) => {
  t.uuid('uuid_col_binary', { useBinaryUuid: true });
});
knex('uuid_table').insert({
  uuid_col_binary:  knex.fn.uuidToBin('3f06af63-a93c-11e4-9797-00505690773f'),
});

binToUuid #

knex.fn.binToUuid(binaryUuid)

Convert a binary uuid (binary(16)) to a string uuid (char(36))

const res = await knex('uuid_table').select('uuid_col_binary');
knex.fn.binToUuid(res[0].uuid_col_binary)