1. SQOOP HCatalog Integration
Venkat Ranganathan
Sqoop Meetup
10/28/13

2. Agenda HCatalog Overview Sqoop HCatalog integration Goals Features
Demo
Benefits

3. HCatalog Overview Table and Storage Management Service for Hadoop
Enables PIG/MR and Hive to more easily share data on the grid
Uses the Hive Meta-store.
Abstracts location and format of the data
Supports reading and writing files in any format for which there is a Hive Serde available.
Now part of Hive.

4. Sqoop HCatalog Integration Goals
Support HCatalog features consistent with Sqoop usage.
Support both imports into and exports from HCatalog table
Enable Sqoop read and write data in various formats.
Automatic table schema mapping
Data fidelity
Support for static and dynamic partition keys

5. Support imports and exports
Allows the HCatalog tables to be either the source or destination of a Sqoop job.
In an HCatalog import, target-dir and warehouse-dir are replaced with the HCatalog table name.
Similarly for exports, the export directory is substituted with the HCatalog table name.

6. File format support
HCatalog integration into Sqoop now enables Sqoop to
Import/Export files of various formats that have hive serde created
Textfiles, Sequence files, RCFiles, ORCFile,…
This makes Sqoop agnostic of the file format used which can change over time based on new innovations/needs.

7. Automatic table schema mapping
Sqoop allows a hive table to be created based on the enterprise data store schema
This is enabled for HCatalog table imports as well.
Automatic mapping with optional user overrides.
Ability to provide a storage options for the newly created table.
All HCatalog primitive types supported

8. Data fidelity
With Text based imports (as in Sqoop hive-import option), the text values have to be massaged so that delimiters are not misinterpreted.
Sqoop provides two options to handle this.
--hive-delims-replacement
--hive-drop-import-delims
Error prone and data is modified to be stored on Hive

9. Data fidelity
With HCatalog table imports to file formats like RCFile, ORCFile etc, there is no need to strip these delimiters in column values.
Data is preserved without any massaging
If the target Hcatalog table file format is Text, then the two options can still be used as before.
--hive-delims-replacement
--hive-drop-import-delims

10. Support for static and dynamic partitioning
HCatalog tables partition keys can be dynamic or static.
Static partitioning keys have values provided as part of the DML (known at Query compile time)
Dynamic partitioning keys have values provided at execution time.
Based on value of a column being imported

11. Support for static and dynamic partitioning
Both types of tables supported during import.
Multiple partition keys per table are supported.
Only one can be a static partition key can be specified (Sqoop restriction).
Only table with one partitioning key can be automatically created.

12. Benefits
Future proof your Sqoop jobs by making them agnostic of file-formats used
Remove additional steps before taking data to the target table format
Preserve data contents

13. Availability & Documentation
Part of Sqoop release
A chapter devoted to HCatalog integration in the User Guide
URL:

14. DEMO

15. Questions?