STX Expression Parser - (Formerly-Online) CSV Data Filter

This page used to be an online CGI demo of the csvtool example found in the STX Expression Parser source distribution. Due to changes in the website in 2012, the online processing has been replaced with pre-generated HTML files. Nevertheless, many CSV data file are still available for downloading. These are formatted to be directly usable with the included csvtool program. The full list can be seen below, it includes only publicly available data.

Each CSV file has a list of column headers. The csvtool can sort the datasets on-the-fly by each available column. The expression parser can be activated by entering a string into the top form. The expression is evaluated for each row of the dataset. Within the expression, the current rows data can be accessed using variables named by the column headers.

There are two methods to use the expression parser. If the expression evaluates to a boolean value, this value determines whether the row gets prints. Thus the expression is used as a data filter. If, however, the expression yields a non-boolean type, then a column "EvalResult" is appended to the CSV dataset. In this column the evaluation results are outputted. It is then possible to sort by the result values.

The following links show some example queries on different CSV data sets. Before viewing these examples it is best to view the original dataset first.

• The CIA World Factbook: Sorted by the population of a country.
• The CIA World Factbook: Countries with a population of at least 100 million and sorted by the land area.
• The CIA World Factbook: Calculate each country's young population and sort by that number.
• OpenGeoDB: Germany cities ordered by state.
• OpenGeoDB: Germany cities located in the "county" of Karlsruhe ordered by name.
• OpenGeoDB: Germany cities with license plate letters "KA".
• MySQL World Countries: Countries sorted by life expectancy.
• MySQL World Countries: Calculate the total "lifetime" of the population by multiplying population times life expectancy. Sorted by this result.
• MySQL World Cities: Largest cities sorted by population.
• MySQL World Cities: Largest cities of the USA sorted by population.
• geonames - Cities > 15000: Largest cities of the USA sorted by population (same query on different dataset).
• geonames - Cities in Germany: Cities in Germany located at least 1500 meters above sea level.
• geonames - Cities in USA: Inhabited cities in USA located at least 2000 meters above sea level.