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Diffstat (limited to 'docs/sql-programming-guide.md')
| -rw-r--r-- | docs/sql-programming-guide.md | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/docs/sql-programming-guide.md b/docs/sql-programming-guide.md index 1b5fde991e..729045b81a 100644 --- a/docs/sql-programming-guide.md +++ b/docs/sql-programming-guide.md @@ -1007,12 +1007,11 @@ let user control table caching explicitly: CACHE TABLE logs_last_month; UNCACHE TABLE logs_last_month; -**NOTE:** `CACHE TABLE tbl` is lazy, similar to `.cache` on an RDD. This command only marks `tbl` to ensure that -partitions are cached when calculated but doesn't actually cache it until a query that touches `tbl` is executed. -To force the table to be cached, you may simply count the table immediately after executing `CACHE TABLE`: +**NOTE:** `CACHE TABLE tbl` is now __eager__ by default not __lazy__. Don’t need to trigger cache materialization manually anymore. - CACHE TABLE logs_last_month; - SELECT COUNT(1) FROM logs_last_month; +Spark SQL newly introduced a statement to let user control table caching whether or not lazy since Spark 1.2.0: + + CACHE [LAZY] TABLE [AS SELECT] ... Several caching related features are not supported yet: |