head
The head method returns a table with a specific number of rows from the beginning of the source table.
Syntax
table.head(size)
Parameters
| Parameter | Type | Description |
|---|---|---|
| size | long | The number of rows to return. |
Returns
A new table with a specific number of rows from the beginning of the source table.
Examples
The following example filters the table to the first two rows.
source = newTable(
stringCol("Letter", "A", "C", "F", "B", "E", "D", "A"),
intCol("Number", NULL_INT, 2, 1, NULL_INT, 4, 5, 3),
stringCol("Color", "red", "blue", "orange", "purple", "yellow", "pink", "blue"),
intCol("Code", 12, 13, 11, NULL_INT, 16, 14, NULL_INT),
)
result = source.head(2)
- source
- result
The following example uses head on a blink table. Note that head treats the blink table like an append-only table, saving the first five rows that were added to the table, and ignoring all following updates.
source = timeTableBuilder().period("PT0.10S").blinkTable(true).build()
result = source.head(5)
