使包含给定数据源路径的任何数据帧的所有缓存数据(和关联的元数据)失效并刷新。
Syntax
refreshByPath(path: str)
参数
| 参数 | 类型 | Description |
|---|---|---|
path |
str | 刷新缓存的路径。 |
示例
# The example below caches a table, and then removes the data.
import tempfile
with tempfile.TemporaryDirectory(prefix="refreshByPath") as d:
_ = spark.sql("DROP TABLE IF EXISTS tbl1")
_ = spark.sql(
"CREATE TABLE tbl1 (col STRING) USING TEXT LOCATION '{}'".format(d))
_ = spark.sql("INSERT INTO tbl1 SELECT 'abc'")
spark.catalog.cacheTable("tbl1")
spark.table("tbl1").show()
# +---+
# |col|
# +---+
# |abc|
# +---+
# Because the table is cached, it computes from the cached data as below.
spark.table("tbl1").count()
# 1
# After refreshing the table by path, it shows 0 because the data does not exist anymore.
spark.catalog.refreshByPath(d)
spark.table("tbl1").count()
# 0
_ = spark.sql("DROP TABLE tbl1")