Create the products/ directory in your tutorial catalog directory.
The products/products.txt file will serve two purposes. It will provide Interchange with the layout of the products database table and it will also provide the data. When Interchange parses the products.txt file, it will expect the first line to contain the names of the fields for the database table (for example, sku, description, price). The first field in the list is expected to be a primary key (unique identifier) for that row. In most cases you are going to use the SKU (stock keeping unit) as the unique identifier for each product.
The product database is handled as a special case since Interchange expects at least the description, price, and product ID (sku) fields. In other words, the products.txt file must at least contain fields named sku, price, and description. You can have other fields too, if you wish.
The simple store that we are going to build will sell tests. You can choose another sample product line, but it is recommended that you keep it simple. Create the file products/products.txt to look like this, with a single tab separating each field:
sku description price 4595 Nice Bio Test 275.45 2623 Stack of Econ Quizzes 1.24 0198 Really Hard Physics Test 1589.34 1299 Ubiquitous diff eq final 37.00
Note: When using tab-delimited files as we are, make sure you have exactly one tab between each field. Some text editors will use spaces to simulate tabs. Interchange expects actual ASCII tab characters; extra spaces or other characters will corrupt your data.
You may notice that the columns don't line up in your text editor. This is the nature of tab-delimited files. Do not try to fix these.