vxquery-cli/src/site/markdown/index.md

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# VXQuery CLI

VXQuery CLI is the command line utility which can be used to execute XQueries 
with ease. No pre-configuration needs to be done in order to execute an XQuery.

---

## Quick Start

***

### Requirements

- Apache VXQuery™ source archive (apache-vxquery-X.Y-source-release.zip)
- JDK >= 1.8
- Apache Maven >= 3.2

***

### Installing

VXQuery CLI comes bundled with the VXQuery source distribution 
(apache-vxquery-X.Y-source-release.zip).

First, run `mvn package`.

```
$ unzip apache-vxquery-X.Y-source-release.zip
$ cd apache-vxquery-X.Y
$ mvn package -DskipTests
```

**vxquery-cli** binaries are located at `vxquery-cli/target/appassembler/bin`. 
There are 2 files in this directory, **vxq** which is the bash executable for unix
based systems and **vxq.bat** for windows systems. Depending on the platform,
suitable executable needs to be selected.

***

### Executing a Query

#### Put the query into a file

VXQuery CLI takes a file location as the argument where this file includes the 
query(statement) to be executed. Suppose the following query needs to be executed.

```
for $x in doc("books.xml")/bookstore/book
where $x/price>30
order by $x/title
return $x/title
```
This statement is querying for the book titles in **books.xml** where price of
the book is greater than 30. Also this query asks for the results to be ordered by
*title* as well. Now, create a file (say **test.xq**) and put the above query as
the content.

**NOTE:** You can replace **books.xml** with any XML file that you have and want 
to run a query on.

#### Execute the query

We need to invoke the matching executable according to your platform (unix/windows) 
inside `vxquery-cli/target/appassembler/bin` directory. To execute the query, run:

```
sh ./apache-vxquery-X.Y/vxquery-cli/target/appassembler/bin/vxq path/to/test.xq
```

***

## Command Line Options

```
 -O N                      : Optimization Level. (default: Full Optimization)
 -available-processors N   : Number of available processors. (default: java's available processors)
 -buffer-size N            : Disk read buffer size in bytes.
 -compileonly              : Compile the query and stop.
 -frame-size N             : Frame size in bytes. (default: 65,536)
 -hdfs-conf VAL            : Directory path to Hadoop configuration files
 -join-hash-size N         : Join hash size in bytes. (default: 67,108,864)
 -local-node-controllers N : Number of local node controllers. (default: 1)
 -maximum-data-size N      : Maximum possible data size in bytes. (default: 150,323,855,000)
 -repeatexec N             : Number of times to repeat execution.
 -rest-ip-address VAL      : IP Address of the REST Server.
 -rest-port N              : Port of REST Server.
 -result-file VAL          : File path to save the query result.
 -showast                  : Show abstract syntax tree.
 -showoet                  : Show optimized expression tree.
 -showquery                : Show query string.
 -showrp                   : Show Runtime plan.
 -showtet                  : Show translated expression tree.
 -timing                   : Produce timing information.
 -timing-ignore-queries N  : Ignore the first X number of quereies.
```

**NOTE:** Normally, CLI starts a local VXQuery Server to execute the query. But,
if you already have a VXQuery Server running, you can send the query to the 
inbuilt *REST Server* running in that server by specifying the **port** and **ip address** 
of the REST Server through options `-rest-ip-address` and `-rest-port`.