Bulk Update

Bulk update is a way to write SQL update statements with in welds.

Bulk updates are accessible on QueryBuilder<T>. To start a bulk update you can call one set operations on your query. set, set_col, set_null, set_manual

set / set_col

set and set_col are functionally identical. They just provide two coding flavors to the same underlying set operation.

To use them start off with a Query just like you would to select your data.

#![allow(unused)]
fn main() {
    let q = Product::where_col(|x| x.name.ilike("% - discontinued") );
}

You can then call set or set_col to convert this query into a bulk update

#![allow(unused)]
fn main() {
    let q = Product::where_col(|x| x.name.ilike("% - discontinued") );

    q.set(|o| o.hidden, true).run(&client).await?;
    // or
    q.set_col(|o| o.hidden.equal(true) ).run(&client).await?;

}

set_null

set_null is just a short hand for set(_, None). It is nice in that it makes your code cleaner to read.

#![allow(unused)]
fn main() {
    let q = Product::where_col(|x| x.name.ilike("% - discontinued") );

    q.set_null(|p| p.category).run(&client).await?;

}

set_manual

Sometimes you need to set a column based on another columns value; for example a calculation. In this scenario set_manual is what you are looking for. It functions in the same way as the other manual sql calls

To use it start off with a query, but this time you can insert a snippit of generic SQL to set the columns value.

#![allow(unused)]
fn main() {
    Order::all()
        .set_manual(|x| x.sell_price, "$.sell_price + ?", (88,))
        .run(&client).await?;
}

NOTE: use ? for all database backends. It will be translated appropriately for the backends being called.