updateView method creates a new table containing a new, formula column for each argument.
updateView, the new columns are not stored in memory. Rather, a formula is stored that is used to recalculate each cell every time it is accessed.
The syntax for the
lazyUpdate methods is identical, as is the resulting table.
updateView is recommended when:
- the formula is fast to compute,
- only a small portion of the data is being accessed,
- cells are accessed very few times, or
- memory usage must be minimized.
For other cases, consider using
lazyUpdate. These methods have different memory and computation expenses.
Formulas to compute columns in the new table; e.g.,
A new table that includes all the original columns from the source table and the newly defined formula columns.
In the following example, a new table containing the columns from the source table plus two new columns,
Y, is created.
source = newTable(
stringCol("A", "The", "At", "Is", "On"),
intCol("B", 1, 2, 3, 4),
intCol("C", 5, 6, 7, 8)
result = source.updateView("X = B", "Y = sqrt(C)")