File Formats: An Introduction

Circulation receives most of its information via data entry (subscriber transactions and so on), and outputs it mainly as documents (bundle tops, renewal notices, etc.). However, in many cases Circulation can import and export information with ASCII files, so that the information can be interfaced with another software product. This appendix documents the required formats for these import and export files.

ASCII (American Standard Code for Information Interchange) files consist of 128 decimal numbers ranging from zero through 127 assigned to letters, numbers, punctuation marks, and the most common special characters. When viewed, ASCII files look much like text files.

A typical ASCII file will contain a certain number of records; each record will be broken down into a certain number of fields (the number of fields will be the same for each record). The file’s format describes the fields and how the computer should differentiate between one field and another.

Some formats are “fixed length”—the computer is told how many places are contained in the first field, how many in the second, and so on. Other formats have a “delimiter”—a certain character such as a comma, space, or pipe symbol (|) that lets the computer know where one field ends and another begins. In this case, each record also has a delimiter, usually a carriage return. Circulation uses both fixed length and delimited formats. Many Circulation formats are space delimited, with quotes around character fields—this is the standard PROGRESS style for formats.

Some of the more complex file formats used by Circulation have several different types of records. Typically, there is a single “batch header” and “batch trailer” record that contains total amounts for the file. In between are multiple “detail” records, one for each transaction.

To interface information between Circulation and other software, you will need to configure the other application so that it can read the Circulation format. In some cases (such as TeleDirect), the file is written in a format specified by the other application. Most (though not all) files are exported or imported from the /dti/exchange/cm directory.

Note: If you have additional database sets, the directory used will be /dti/exchange/<dblist>. For example, if you have a separate set of Circulation databases called “cmtest”, the directory used will be /dti/exchange/cmtest.

Note:

If importing masked credit card numbers (credit card numbers where only the last four digits are readable for security purposes), you must use an asterisk (“*”) for masked characters.

An example of a pipe-delimited file is shown below.

An example of a fixed-length file is shown below.