R: Randomly Sample Rows from a Spark DataFrame

sdf_sample {sparklyr} | R Documentation

## Randomly Sample Rows from a Spark DataFrame

### Description

Draw a random sample of rows (with or without replacement) from a Spark DataFrame.

### Usage

    sdf_sample(x, fraction = 1, replacement = TRUE, seed = NULL)

### Arguments

`x` | An object coercable to a Spark DataFrame.
`fraction` | The fraction to sample.
`replacement` | Boolean; sample with replacement?
`seed` | An (optional) integer seed.

### Transforming Spark DataFrames

The family of functions prefixed with `sdf_` generally access the Scala Spark DataFrame API directly, as opposed to the `dplyr` interface which uses Spark SQL. These functions will 'force' any pending SQL in a `dplyr` pipeline, such that the resulting `tbl_spark` object returned will no longer have the attached 'lazy' SQL operations. Note that the underlying Spark DataFrame does execute its operations lazily, so that even though the pending set of operations (currently) are not exposed at the R level, these operations will only be executed when you explicitly `collect()` the table.

### See Also

Other Spark data frames: `sdf_copy_to`, `sdf_partition`, `sdf_register`, `sdf_sort`

[Package sparklyr version 0.8.2 Index]