Github user dyozie commented on a diff in the pull request:

    https://github.com/apache/incubator-hawq-docs/pull/46#discussion_r85794241
  
    --- Diff: pxf/HDFSWritablePXF.html.md.erb ---
    @@ -0,0 +1,410 @@
    +---
    +title: Writing Data to HDFS
    +---
    +
    +The PXF HDFS plug-in supports writable external tables using the 
`HdfsTextSimple` and `SequenceWritable` profiles.  You might create a writable 
table to export data from a HAWQ internal table to HDFS.
    +
    +This section describes how to use these PXF profiles to create writable 
external tables.
    +
    +**Note**: You cannot directly query data in a HAWQ writable table.  After 
creating the external writable table, you must create a HAWQ readable external 
table accessing the HDFS file, then query that table. ??You can also create a 
Hive table to access the HDFS file.??
    +
    +## <a id="pxfwrite_prereq"></a>Prerequisites
    +
    +Before working with HDFS file data using HAWQ and PXF, ensure that:
    +
    +-   The HDFS plug-in is installed on all cluster nodes. See [Installing 
PXF Plug-ins](InstallPXFPlugins.html) for PXF plug-in installation information.
    +-   All HDFS users have read permissions to HDFS services and that write 
permissions have been restricted to specific users.
    +
    +## <a id="hdfsplugin_writeextdata"></a>Writing to PXF External Tables
    +The PXF HDFS plug-in supports writable two profiles: `HdfsTextSimple` and 
`SequenceWritable`.
    +
    +Use the following syntax to create a HAWQ external writable table 
representing HDFS data: 
    +
    +``` sql
    +CREATE EXTERNAL WRITABLE TABLE <table_name> 
    +    ( <column_name> <data_type> [, ...] | LIKE <other_table> )
    +LOCATION ('pxf://<host>[:<port>]/<path-to-hdfs-file>
    +    
?PROFILE=HdfsTextSimple|SequenceWritable[&<custom-option>=<value>[...]]')
    +FORMAT '[TEXT|CSV|CUSTOM]' (<formatting-properties>);
    +```
    +
    +HDFS-plug-in-specific keywords and values used in the [CREATE EXTERNAL 
TABLE](../reference/sql/CREATE-EXTERNAL-TABLE.html) call are described in the 
table below.
    +
    +| Keyword  | Value |
    +|-------|-------------------------------------|
    +| \<host\>[:\<port\>]    | The HDFS NameNode and port. |
    +| \<path-to-hdfs-file\>    | The path to the file in the HDFS data store. |
    +| PROFILE    | The `PROFILE` keyword must specify one of the values 
`HdfsTextSimple` or `SequenceWritable`. |
    +| \<custom-option\>  | \<custom-option\> is profile-specific. These 
options are discussed in the next topic.|
    +| FORMAT 'TEXT' | Use '`TEXT`' `FORMAT` with the `HdfsTextSimple` profile 
when \<path-to-hdfs-file\> will reference a plain text delimited file. The 
`HdfsTextSimple` '`TEXT`' `FORMAT` supports only the built-in 
`(delimiter=<delim>)` \<formatting-property\>. |
    +| FORMAT 'CSV' | Use '`CSV`' `FORMAT` with `HdfsTextSimple` when 
\<path-to-hdfs-file\> will reference a comma-separated value file.  |
    +| FORMAT 'CUSTOM' | Use the `'CUSTOM'` `FORMAT` with the 
`SequenceWritable` profile. The `SequenceWritable` '`CUSTOM`' `FORMAT` supports 
only the built-in `(formatter='pxfwritable_export)` (write) and 
`(formatter='pxfwritable_import)` (read) \<formatting-properties\>.
    +
    +**Note**: When creating PXF external tables, you cannot use the `HEADER` 
option in your `FORMAT` specification.
    +
    +## <a id="profile_hdfstextsimple"></a>Custom Options
    +
    +The `HdfsTextSimple` and `SequenceWritable` profiles support the following 
\<custom-options\>:
    --- End diff --
    
    Change <custom-options> to "<custom-option> values"?


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