Advanced Query on TRAINS / IDB Introduction
The Advanced Query tool gives users the ability to construct sophisticated queries using the data available in UN COMTRADE, TRAINS, and WTO IDB databases.In this module, we are covering the data retrieval from TRAINS and WTO IDB databases only, UN COMTRADE being trade oriented database (see Advanced Query on UN COMTRADE if you want to learn how to retrieve trade flow information).
In principle, Advanced Queries work the same way as Quick Search: you define query parameters and submit your job to see results. However, there are a few differences:
- Quick Search offers separate tools for working with different databases. Advanced Query is common tool for querying different databases (UN COMTRADE, TRAINS and IDB). Therefore, you must start any query by specifying the database to be used;
- Advanced Query can be saved and reused. This is particularly useful for complex queries and reports that need to be reproduced on a regular basis.
- While a Quick Search deals with only one item for most dimensions (reporter, partner, product, year), you can include several reporters, partners, products and years in a single Advanced Query.
- Product and country groups allow retrieving aggregated results.
- Quick Search allow for retrieving raw data only as they are stored in the databases. In Advanced Query, you can select and retrieve tariffs for products defined using various nomenclatures and mix product categories from different Tiers.
- While Quick Search are immediately processed, Advanced Queries are queued on WITS server. Compared to Quick Search, Advanced Queries are generally much larger and require more time to be processed. Once you submit an Advanced Query, you can check the status of your job periodically to find-out when results are ready.
- One main disadvantage of Advanced Query vis-a-vis Quick Query (covered in previous modules) is that maximum level of product detail of trade flows is at 6-digit harmonized system classification whereas in a Quick Database Query of TRAINS and WTO, output is available at the tariff line level (e.g., 8- or 10-digits.)
Next: Opening the Tool
WITS Online Help
The World Bank, 2010