הערה
הגישה לדף זה מחייבת הרשאה. באפשרותך לנסות להיכנס או לשנות מדריכי כתובות.
הגישה לדף זה מחייבת הרשאה. באפשרותך לנסות לשנות מדריכי כתובות.
Invalidates and refreshes all the cached data and metadata of the given table.
Syntax
refreshTable(tableName: str)
Parameters
| Parameter | Type | Description |
|---|---|---|
tableName |
str | Name of the table to get. Can be qualified with catalog name. |
Examples
# The example below caches a table, and then removes the data.
import tempfile
with tempfile.TemporaryDirectory(prefix="refreshTable") 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, it shows 0 because the data does not exist anymore.
spark.catalog.refreshTable("tbl1")
spark.table("tbl1").count()
# 0
# Using the fully qualified name for the table.
spark.catalog.refreshTable("spark_catalog.default.tbl1")
_ = spark.sql("DROP TABLE tbl1")