Number of rows affected by last update

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

.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
#> 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
#> 1: 3
.Last.updated
#> [1] 2