flutter moor - update specific column in specific row of table

I need to replace a value in specific column of specific row in moor database, but I don't know it's query. can you bring me an example?

Here is the answer what you wanted to do is:

Future moveImportantTasksIntoCategory(Category target) {
  // for updates, we use the "companion" version of a generated class. This wraps the
  // fields in a "Value" type which can be set to be absent using "Value.absent()". This
  // allows us to separate between "SET category = NULL" (`category: Value(null)`) and not
  // updating the category at all: `category: Value.absent()`.
  return update(todos)
      ..where((t) => t.title.like('%Important%')))
      ..write(TodosCompanion(category: Value(target.id)));
}

If you can't understand it. Check my example:

  updateHeaderId(String customerCode, int headerId) {
    update(offlineOrderLines)
      ..where((tbl) => tbl.custCode.equals(customerCode))
      ..write(OfflineOrderLinesCompanion(headerId: Value(headerId)));
  }

In the above example, I want to change headerId of particular customerCode. Do let me know if you have any questions.