Recipe 11.16. Numbering Query Output Rows Sequentially


Problem

You want to number the rows of a query result.

Solution

If you're writing your own program, just add the row numbers yourself.

Discussion

A type of sequence that has nothing to do with the contents of your database is to number output rows from a query. When working within an API, you can number the rows by maintaining a counter and displaying its current value with each row's contents. Here is an example in Python, using the insects table. It displays a simple numbered list of the distinct values in the origin column of the table:

cursor = conn.cursor () cursor.execute ("SELECT DISTINCT origin FROM insect") count = 1 for row in cursor.fetchall ():   print count, row[0]   count = count + 1 cursor.close () 

See Also

The mysql program provides no explicit row-numbering facilities, although you can use a user-defined variable to include an extra row number column in a query's output. Another way to produce results that may be suitable for your purposes is to filter mysql output through another program that adds row numbers. Section 1.27 describes these techniques.




MySQL Cookbook
MySQL Cookbook
ISBN: 059652708X
EAN: 2147483647
Year: 2004
Pages: 375
Authors: Paul DuBois

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