Number of rows affected by last update

Returns number of rows affected by last := or set().

Usage

.Last.updated

Value

Integer.

Details

Be aware that in the case of duplicate indices, multiple updates occur (duplicates are overwritten); .Last.updated will include all of the updates performed, including duplicated ones. See examples.

See also

:=

Examples

d = data.table(a=1:4, b=2:5)
d[2:3, z:=5L]
#>        a     b     z
#>    <int> <int> <int>
#> 1:     1     2    NA
#> 2:     2     3     5
#> 3:     3     4     5
#> 4:     4     5    NA
.Last.updated
#> [1] 2

# updated count takes duplicates into account #2837
DT = data.table(a = 1L)
DT[c(1L, 1L), a := 2:3]
#>        a
#>    <int>
#> 1:     3
.Last.updated
#> [1] 2