Delimiter-separated values

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Formats that use delimiter-separated values store two-dimensional arrays of data by separating the values in each row with specific delimiter characters. Most database and spreadsheet programs are able to read or save data in a delimited format.

Any character may be used to separate the values, but the most common delimiters are the comma, tab, and colon. The vertical bar (also referred to as pipe) and space are also sometimes used. For example, in a comma-separated values (CSV) file the data items are delimited using commas. Column headers are sometimes included as the first line, and each subsequent line is a row of data. The lines are separated by newline and/or carriage return characters.

Typically a delimited file format is indicated by a specification. Some specifications provide conventions for avoiding delimiter collision, others do not. Comma- and space-separated formats often suffer from this problem, since in many contexts those characters are legitimate parts of a data field. Most such files avoid delimiter collision either by surrounding all data fields in double quotes, or only quoting those data fields that contain the delimiter character.

Due to their widespread use, comma- and tab-delimited text files can be opened by most spreadsheet programs, and statistical analysis tools such as PSPP, without the user designating which delimiter has been used.

The major problem with tab-delimited text files is that tabs are invisible, and difficult to distinguish from spaces; therefore, there are sometimes problems with the files being corrupted when people try to edit them by hand. The major problem with comma-delimited text files is that commas are common in field data for many applications, which means that some form of quoting and/or escaping mechanism must be used. A common alternative is to choose another punctuation character as a delimiter, one which is less likely to occur in field data than comma -- common choices include pipe (|) and hash (#), but the best choice depends on the kind of data the application deals with.

For example, the following fields in each record are delimited by commas, and each record by newlines:

"Date","Pupil","Grade"
"25 May","Bloggs, Fred","C"
"25 May","Doe, Jane","B"
"15 July","Bloggs, Fred","D"

ASCII includes several control characters that are intended to be used as delimiters. They are: 28 file separator, 29 group separator, 30 record separator, 31 unit separator. Use of these characters has not achieved widespread adoption; some systems have replaced their control properties with more accepted controls such as CR/LF and TAB.