Because you can't :)
Keep in mind what is really happening here. The ESQL logicsheet is turning
all of this into java code. What kind of java code probably happens with
the esql:query tag? Well, it probably needs to obtain a String which it
can then pass into JDBC as the query, righ?. Now, try this in java:
String query = if (...) { ... } else { ... }
See the problem?
However, the problem suggests the solution. You CAN do it, but only if you
make your if/else into an expression, using the question mark operator,
e.g.,
<xsp:expr>(id_blog_news == null) ? ... : ... </xsp:expr>
Better, though is to just pull the entire query and if/else block outside
the esql code, e.g.,
String sql;
if (id_blog_news == null) {
sql = "SELECT .....";
} else {
sql = ....
}
then you can do
<esql:query>
<xsp:expr>sql</xsp:expr>
</esql:query>
You can also put your if-else around the entire esql:execute-query block,
that is, you can have one esql:connection around all of your individual
queries, for what small savings in code that is.
Finally, though, keep in mind that your dynamic SQL code potentially
provides opportunities for hackers to modify your SQL in ways you did not
intend by what they supply in the request parameters. So you might be
better off going back to your first code that does an if/else around the
whole SQL block, and using <esql:parameter> instead of inlining SQL using
<xsp:expr>.
-Christopher
|---------+---------------------------->
| | olivier demah |
| | <[EMAIL PROTECTED]|
| | com> |
| | |
| | 04/05/2004 10:53 |
| | AM |
| | Please respond to|
| | users |
| | |
|---------+---------------------------->
>--------------------------------------------------------------------------------------------------------------|
|
|
| To: [EMAIL PROTECTED]
|
| cc:
|
| Subject: Conditionnal esql-query ?
|
>--------------------------------------------------------------------------------------------------------------|
....
this one is not ok :
<blog_addnews>
<xsp:logic>
String id_blog_user = request.getParameter("id_blog_user");
String id_blog_news = request.getParameter("id_blog_news");
if ( id_blog_user == null) {
id_blog_user = <xsp-session-fw:getxml context="authentication"
as="string" path="/authentication/data/id_blog_user"/> ;
}
<esql:connection>
<esql:pool>mblog_pg</esql:pool>
<esql:execute-query>
<esql:query>
if (id_blog_news == null) {
SELECT * FROM blog_news WHERE blog_news.id_blog_user =
'<xsp:expr>id_blog_user</xsp:expr>'
} else {
SELECT * FROM blog_news WHERE blog_news.id_blog_user =
'<xsp:expr>id_blog_user</xsp:expr>' AND id_blog_news =
'<xsp:expr>id_blog_news</xsp:expr>'
}
</esql:query>
<esql:results>
<esql:row-results>
<blog_new>
<id_blog_news><esql:get-int
column="id_blog_news"/></id_blog_news>
<id_blog_user><esql:get-string
column="id_blog_user"/></id_blog_user>
<news_title><esql:get-string
column="news_title"/></news_title>
<news_text><esql:get-string
column="news_text"/></news_text>
<news_image><esql:get-string
column="news_image"/></news_image>
<news_date_creation><esql:get-string
column="news_date_creation"/></news_date_creation>
<news_date_modify><esql:get-string
column="news_date_modify"/></news_date_modify>
</blog_new>
</esql:row-results>
</esql:results>
</esql:execute-query>
</esql:connection>
</xsp:logic>
</blog_add>
but why cant i just do a simple if just on the esql-query part ?
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
