Update

Table::update() returns an Update builder for adding or rewriting columns. Set a column to the result of an expression with .set, optionally restrict the rows touched with .filter, and run with .execute().

Assume a live runtime and the trades table

use rayforce::{col, Runtime, Table, Value};
let _rt = Runtime::new()?;
let t = trades(); // sym / price / size — see the Overview

Builder methods

Method	Purpose
.set(name, expr)	set/add a column from an expression
.filter(pred)	restrict the update to matching rows
.execute()	compile and run, returning Result<Table>

Add a computed column

.set with a new column name appends a derived column. Here notional is price * size:

let r = t
    .update()
    .set("notional", col("price") * col("size"))
    .execute()?;
println!("{r}");

┌──────┬───────┬──────┬───────────────┐
│ sym  │ price │ size │   notional    │
│ SYM  │  F64  │ I64  │      F64      │
├──────┼───────┼──────┼───────────────┤
│ AAPL │ 100.0 │ 10   │ 1000.0        │
│ MSFT │ 200.0 │ 20   │ 4000.0        │
│ AAPL │ 110.0 │ 30   │ 3300.0        │
│ GOOG │ 300.0 │ 40   │ 12000.0       │
│ MSFT │ 210.0 │ 50   │ 10500.0       │
├──────┴───────┴──────┴───────────────┤
│ 5 rows (5 shown) 4 columns (4 shown)│
└─────────────────────────────────────┘

Rewrite an existing column

Using an existing name overwrites that column in place. Here we apply a 10% markup to price:

let r = t.update().set("price", col("price") * 1.1f64).execute()?;

Conditional update

Add .filter to update only the matching rows. Other rows keep their original value:

let r = t
    .update()
    .set("price", col("price") * 1.1f64)
    .filter(col("sym").eq("MSFT"))
    .execute()?;

Continue with Insert to append rows.