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Posted to commits@drill.apache.org by br...@apache.org on 2015/09/16 01:24:19 UTC
[2/5] drill git commit: remove comment markers
remove comment markers
Project: http://git-wip-us.apache.org/repos/asf/drill/repo
Commit: http://git-wip-us.apache.org/repos/asf/drill/commit/26e9af6b
Tree: http://git-wip-us.apache.org/repos/asf/drill/tree/26e9af6b
Diff: http://git-wip-us.apache.org/repos/asf/drill/diff/26e9af6b
Branch: refs/heads/gh-pages
Commit: 26e9af6b56b99265db9453fba126401bc8c98c03
Parents: 27c736a
Author: Kristine Hahn <kh...@maprtech.com>
Authored: Wed Sep 9 09:59:35 2015 -0700
Committer: Kristine Hahn <kh...@maprtech.com>
Committed: Tue Sep 15 16:19:29 2015 -0700
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_docs/data-sources-and-file-formats/040-parquet-format.md | 6 +++---
.../query-a-file-system/020-querying-parquet-files.md | 4 ++--
2 files changed, 5 insertions(+), 5 deletions(-)
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http://git-wip-us.apache.org/repos/asf/drill/blob/26e9af6b/_docs/data-sources-and-file-formats/040-parquet-format.md
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diff --git a/_docs/data-sources-and-file-formats/040-parquet-format.md b/_docs/data-sources-and-file-formats/040-parquet-format.md
index 449e138..5a0e67d 100644
--- a/_docs/data-sources-and-file-formats/040-parquet-format.md
+++ b/_docs/data-sources-and-file-formats/040-parquet-format.md
@@ -20,9 +20,9 @@ Apache Drill includes the following support for Parquet:
## Reading Parquet Files
When a read of Parquet data occurs, Drill loads only the necessary columns of data, which reduces I/O. Reading only a small piece of the Parquet data from a data file or table, Drill can examine and analyze all values for a column across multiple files. You can create a Drill table from one format and store the data in another format, including Parquet.
-<!-- ## Caching Metadata
+## Caching Metadata
-For performant querying of a large number of files, Drill can take advantage of metadata, such as the Hive metadata store, and includes the capability of generating a metadata cache for performant querying of thousands of Parquet files. The metadata cache is not a central caching system, but simply one or more files of metadata. Drill generates and saves a cache of metadata in each directory in nested directories. You trigger the generation of metadata caches by running the REFRESH TABLE METADATA command, as described in [Querying Parquet Files]({{site.baseurl}}/docs/querying-parquet-files/).
+For performant querying of a large number of files, Drill 1.2 and later can take advantage of metadata, such as the Hive metadata store, and includes the capability of generating a metadata cache for performant querying of thousands of Parquet files. The metadata cache is not a central caching system, but simply one or more files of metadata. Drill generates and saves a cache of metadata in each directory in nested directories. You trigger the generation of metadata caches by running the REFRESH TABLE METADATA command, as described in [Querying Parquet Files]({{site.baseurl}}/docs/querying-parquet-files/).
After generating the metadata cache, Drill performs the following tasks during the planning phase for a query on a directory of Parquet files:
@@ -33,7 +33,7 @@ After generating the metadata cache, Drill performs the following tasks during t
* Summarizes the information from the footers in a single metadata cache file.
* Stores the metadata cache file at each level that covers that particular level and all lower levels.
-At execution time, Drill reads the actual files. At planning time, Drill reads only the metadata file. -->
+At execution time, Drill reads the actual files. At planning time, Drill reads only the metadata file.
## Writing Parquet Files
CREATE TABLE AS (CTAS) can use any data source provided by the storage plugin. To write Parquet data using the CTAS command, set the session store.format option as shown in the next section. Alternatively, configure the storage plugin to point to the directory containing the Parquet files.
http://git-wip-us.apache.org/repos/asf/drill/blob/26e9af6b/_docs/query-data/query-a-file-system/020-querying-parquet-files.md
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diff --git a/_docs/query-data/query-a-file-system/020-querying-parquet-files.md b/_docs/query-data/query-a-file-system/020-querying-parquet-files.md
index b166386..7364969 100644
--- a/_docs/query-data/query-a-file-system/020-querying-parquet-files.md
+++ b/_docs/query-data/query-a-file-system/020-querying-parquet-files.md
@@ -3,7 +3,7 @@ title: "Querying Parquet Files"
parent: "Querying a File System"
---
-<!-- Drill extends SQL for performant querying of a large number, thousands or more, of Parquet files. By including the following command in a query, you trigger the generation of metadata files in the directory of Parquet files and its subdirectories:
+Drill 1.2 and later extends SQL for performant querying of a large number, thousands or more, of Parquet files. By including the following command in a query, you trigger the generation of metadata files in the directory of Parquet files and its subdirectories:
REFRESH TABLE METADATA <path to table>
@@ -15,7 +15,7 @@ You can query nested directories from any level. For example, you can query a su
TBD (fill in when the feature is ready)
-## Sample Parquet Files -->
+## Sample Parquet Files
The Drill installation includes a `sample-data` directory with Parquet files
that you can query. Use SQL syntax to query the `region.parquet` and
`nation.parquet` files in the `sample-data` directory.