DBI_QUERY -- make simple requests to a database.

Each query consist of two parts: a query statement (mostly is a SELECT statement) and output formatting filters. SQL statement starts just after the leading %DBI_QUERY{...}% declaration. The filters are defined by .header, .body, and .footer keywords each starting at the beginning of line. Their meaning shall be obvious from their name:

Declaration	Description
.header	It is prepended to the query output once.
.body	It is repeated for each row of data being fetched from the database.
.footer	It is appended to the query output.

Parameters

Parameter	Description	Default	Required
"db_identifier"	Database ID as defined in the plugin configuration. See DatabaseContrib configuration section.	none	required
subquery="name"	Defines a subquery which does not produce immediate result but could be used from inside another query -- see %DBI_SUBQUERY%	none	optional
unquoted="col1 col2 ..."	List of columns to be left unquoted in the output. Read more in Quoting of Values section.	none	optional
protected="col1 col2 ..."	List of columns to be protected from processing by Foswiki engine.	none	optional

A small note on protected parameter. Say, one has an arbitrary data in a displayed column which could contain any kind of text strings. What happens if such a string looks like a Foswiki variable or macro? It's gonna be expaded for sure. Adding a column to the protected list makes data from this column displayed as is, unmodified.

DBI_SUBQUERY -- call a %DBI_XXX% subquery

%DBI_SUBQUERY{"name"}% (aliased as %DBI_EXEC%) doesn't exist as a separate variable but only as a part of header/body/footer processing mechanism. It's functionality is described in Variable Expansion and Subqueries sections of DBIQueryPlugin documentation.

Examples

%DBI_QUERY{"db_identifier" ...}%
SELECT ...
.header
head
.body
%column%
%DBI_SUBQUERY{"name"}%
.footer
footer
%DBI_QUERY%

Related

• DBI_CALL -- directly call a subquery.
• DBI_CODE -- storing a script for %DBI_DO%
• DBI_DO -- do complex processing with Perl code.