Replace Command


Replaces each found record in a database with the new field values.

To replace records in a database, use a web browser to link to a URL containing the Replace command (alternately, you may embed a [Replace] context into a template). Whenever WebDNA receives a Replace command, it immediately searches for the specified records in the database, and replaces those records' fields with the named field values.

SQL/ODBC Note: To replace records in an ODBC-compliant table, use the [SQL] context.

Example (normally you would link to a URL or form containing the following information):

The database "SomeDatabase.db" opens and all records whose name field is "Grant" are found. The field names "name" is set to "John," "address" is set to "1492 Somewhere Lane," and "zip" is set to "90000."

Any fieldnames not existing in the database are ignored, and any fields you do not specify are left blank in the new record. Certain letters are illegal, such as <tab> or <carriage return>, so they are converted to <space> and <soft return> before being added to the database. Some computers use the two-character sequence <carriage return><line feed> to indicate a single end of line, which is converted automatically to a single <soft return> character before being added to the database.

You may specify a relative or full URL to the database file, as in "/WebCatalog/Folder/SomeDatabase.db" or "../SomeDatabase.db". The path to the database is always relative to the template URL, so if the database is in the same folder as the template the path would be "SomeDatabase.db", and if the database were one folder up then the path would be "../SomeDatabase.db".

Note: You may force the visitor to enter something into a field by using the RequiredFields parameter in the URL. Setting RequiredFields=name+address+city displays an error message if the visitor forgets to enter text into any of those 3 fields. RequiredFields works for all commands, not just this one.

Here are some equivalent ways to send the same command:
HTML Source Description
<a href="xx.tpl?command=Replace&db=SomeDatabase.db&name=John&address=1234%20Somewhere&eqNAMEdata=Grant">
Hyperlink command
<form method="POST" action="xx.tpl">
<input type="hidden" name="command" value="Replace">
<input type="hidden" name="template" value="xx.tpl">
<input type="hidden" name="db" value="SomeDatabase.db">
<input name="eqNAMEdata" value="John">
<input name="name">
<input name="address">
<input type="submit">
Form-based command

Parameters for Replace:
Parameter Description


(Optional) "T" if you want a new record to be added to the end of the database in the case where no records were found to be replaced.

User Contributed Notes

Copyright © 2008 WebDNA Software Corporation, Inc.