Visualising Australia's radio communication links

Mark Hansen suggested I create the Aussie version of his NZ wireless map, so I did 💁

Please interact with the map by clicking on icons and zooming in and out. Sydney Tower sure has a lot of radio links!

The full screen version is available here.

Instructions and code are available in my Github repository.

Tech used: PostgresSQL, Visual Studio Code, Google Fusion Tables

Importing CSV/TSV with Teradata SQL Assistant

1. Set up Teradata to match the format of your text file
1. To choose the delimiter:
• Under Tools → Options, go to Export/Import and select one of the options in 'Use this delimiter between columns', e.g. tab, comma, or pipe
2. To skip the first row, e.g. a header line:
• Under Tools → Options, go to Import and select 'Ignore the first record in the import file (Skip Header)'
2. Create the table in Teradata
1. Run the command:
• CREATE TABLE <TableName> (<column1> <datatype>, <column2> <datatype>, ...) PRIMARY INDEX (<column1>);
3. Import the file
1. Go to File → Import Data
2. Run the command:
• INSERT INTO <TableName> VALUES(?,?);
3. where the number of ? matches the number of columns in your data file
3. In the popup window, Open your file
4. Unset Import mode by selecting File → Import Data
4. Check that your table has loaded correctly
1. Run the command:
• SELECT * FROM <TableName>;

Find the space used by a Hive table

There are a few ways to identify the space used by a Hive table.

Unfortunately, my Hive wouldn't accept these commands (and I haven't worked out why...):

• hive > SHOW TBLPROPERTIES <TableName>("rawDataSize")
• hive > DESCRIBE EXTENDED <TableName>

So I resorted to using the file system shell:

• hadoop fs -du -h <URI>