Define Hive Table Properties
Use the Hive Table Editor to define table properties. This procedure assumes you are working in a physical model, with Hive defined as the target server.
To define properties for a Hive table:
- On the Model menu, click Tables .
The Hive Table Editor opens.
- In the navigation grid, select the table that you want to define and work with the following options:
Note: Click New
on the toolbar to create a new table. Use the Enter filter text box to filter a very large list of tables to quickly locate the one that you want to define.
- Physical Name
Specifies the physical name of the table. Change the physical name of the table in this field.
- Database
Specifies the database to which the table belongs. Select a database from the drop-down list or click New
to create one.
- Table Type
Specifies the type of the table. Select whether the table is a managed or external table.
- Temporary
Indicates that the table is temporary.
- Physical Only
Specifies whether the table is suppressed from a logical model and appears in a physical model only.
- Touch
Specifies whether you want to read metadata and write it back. This is similar to causing pre/post execute hooks to fire.
- Generate
Generates SQL during forward engineering. Clear the check box if you do not want to generate SQL.
- Click the General tab and work with the following options:
- Physical Name
Detects the Physical Name of the table. Set the inheritance and override options here.
- Location
Indicates that a specific distributed file system directory must be used to store data files.
- Table Properties
Lets you specify additional table properties.
- Like Table
Lets you specify the table from which to copy table definition exactly (without copying its data). The new table contains no rows.
- Like View
Lets you specify the view from which to copy view definition exactly (without copying its data). It creates a table by adopting the schema of a view (fields and partition columns) using defaults for SerDe and file formats.
- Concatenate
Specifies whether multiple small RC or ORC files contained in a table or partition should be merged into larger files.
- Compact
Specifies whether data should be compacted periodically to save space and optimize data access. Select the type of compaction from the drop-down list:
- MAJOR
Takes one or more delta files and the base file for the bucket and rewrites them into a new base file per bucket.
- MINOR
Takes a set of existing delta files and rewrites them to a single delta file per bucket.
- Overwrite Table Properties
Lets you specify the table properties that can be overwritten.
- Click the Storage tab and work with the following options:
- Fields Terminated By
Specifies a delimiter for structure fields. You can include any single character, but the default is '\001'.
- Fields Escaped By
Specifies the escape sequence.
- Collection Items Terminated By
Specifies a delimiter for array items. You can include any single character, but the default is '\002'.
- Map Keys Terminated By
Specifies a delimiter for map keys. You can include any single character, but the default is '\003'.
- Lines Terminated By
Specifies a delimiter for map keys. You can include any single character, but the default is '\n'.
- Null Defined As
Specifies a custom NULL format apart from the Stored As options mentioned above.
- Serde Handler Class
Specifies the name of a Java class that implements the Hive SerDe interface.
- Stored As
Specifies the type of file in which data is to be stored. The file can be a TEXTFILE, SEQUENCEFILE, RCFILE, ORC, PARQUEST, or AVRO.
- Input Format
Lets you specify your own Java class if you want Hive to read from a different file format. The value of this property depends on the Stored As value.
- Output Format
Lets you specify your own Java class if you want Hive to write to a different file format. The value of this property depends on the Stored As value.
- Stored By
Specifies the name of a Java class that implements the Hive StorageHandler interface.
- Serde Properties
Specifies SerDe properties to be associated with the storage handler class.
- Click the Bucketing and Partition tab and work with the following options:
- Bucket Columns
Select the columns based on which you want to distribute rows across buckets.
- Bucket Sorted Columns
Select the column based on which you want the rows to be sorted within each bucket.
- Bucket Option
- Number of Buckets
Specifies the number of buckets to be created.
- Partition Elements
- Name
Specifies the name of the partition.
- Physical Data Type
Specifies the physical data type for the partition element. You can change the data type using the drop-down. The drop-down list contains the data types related to the current domain.
- Comment
Displays the notes entered by the user. Click the Edit icon to add comments.
- Partitions
Specifies partition specification and location once partition elements are created.
- Click the Skewed Options tab and work with the following options:
- Skewed Columns
Lets you select the columns that you want to skew.
- Skewed Option
Specifies whether a skewed table uses the list bucketing feature, which creates subdirectories for skewed values.
- Skewed Column Values
Specifies the values based on which you want to skew the table.
- Click the Statistics tab to view the following options:
- Number Of Partitions
Specifies the number of partitions the table has.
- Number Of Files
Specifies the number of files the table has.
- Number Of Rows
Specifies the number of rows the table has
- Raw Data Size
Specifies the size of the original dataset.
- Total Size
Specifies the amount of storage the original dataset takes.
Note: The above information is fetched only when reverse engineering from database is done and you have chosen to store statistical information.
- Click the Volumetrics tab and work with the following options:
- Initial Row Count
Defines row count for the table. Enter a value in the field.
- Max Rows
Defines row sizing for the table. Enter a value in the field.
- Growth By Month
Defines growth increments for the table. Enter a value in the field.
- Work with the other tabs in the editor to access additional design features, for example:
- Preview the forward engineering script for a table in the SQL tab.
- Specify validation rules in the Validation tab.
- Define table permissions using the Permission tab.
- Work with style sheets to format the font used in the display of the table in the Styletab.
- Specify the icon style to use for the table in the Icon tab.
- Specify the order of DDL generation in the Object Creation Order tab.
- (Optional) Click the Comment tab and enter any comments that you want to associate with the object.
- (Optional) Click the Where Used tab to view where the object is used within the model.
- (Optional) Click the UDP tab to work with user-defined properties for the object.
- (Optional) Click the History tab to view the history information for the object.
- (Optional) Click the Notes tab to view and edit user notes.
- (Optional) Click the Extended Notestoview or edit additional user notes.
- Click Close.
The table is defined and the Hive Table Editor closes.
For more information on table properties, refer to Hive documentation.
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