Editor.Where()

Chandler242

Hello,

Since the first parameter for Editor.Where() is column name, I assume that there isn't way to do a condition that doesn't involve column name but only a constant, such as a function input parameter. Or there is a way other than using .Where()?

Thank you,

John Li

allan

Hi John,

You can use the result of an SQL function as part of the query by using a function for the condition but the first parameter would still be a column.

Allan

Chandler242

Hey Allan,

I might have misunderstood your response. But what I intended to do is

in

 public ActionResult RptDynamicSection(int HwyID)
{
Editor.()
 .Field(new Field("Table.HighwayID"))

.Where ()
}

to construct .Where to get the following query condition:

(HwyID=0)  OR (HwyID>0 AND Table.HighwayID=HwyID)

There is no "0" value in the table. By doing above I try to get all the records with "0" value.

I wonder if there is a solution with using .Where() or anything else.

Regards,

John Li

allan

public ActionResult RptDynamicSection(int HwyID)
{
Editor.()
  .Field(new Field("Table.HighwayID"))
  .Where( q => {
    q.Where( r => {
      r.Where("HwyID", 0);
      r.OrWhere( s => {
        s.Where("HwyID", 0, ">");
        s.Where("Table.HighwayID", "HwyID", "=", false);
      });
  })
}

Is how that could be done with our database class. The false parameter on the last Where condition just ensures that the value isn't bound - see docs here.

Allan

Chandler242

Hello Allan,

I had tried, and tried again this morning. I kept getting DataTables message "Invalid column name 'HwyID' " . I guess the message makes sense because HwyID is not a table column name.

I read the linked doc and .NET API doc several times they all state that the first parameter of .Where() is a table name. I must still be missing something. Could you shed more light on this?

Regards,

John

allan

I guess the message makes sense because HwyID is not a table column name.

What is it then? I took it from your line above.

The first parameter for Where is the column name, but it can be prefixed by a table name.

Allan

Chandler242

Hey Allan,

Sorry for the confusion. "HwyID" is a parameter in method

public ActionResult RptDynamicSection(int HwyID)

It is just a parameter, not associated with any specific table column.

Thank you,

John

allan

Oh - sorry! I even copy / pasted it in the controller I showed above!

That makes things much easier then - since it effectively means no query when HwyID == 0, so we can apply a condition on it when it is greater than 0:

public ActionResult RptDynamicSection(int HwyID)
{
Editor.()
  .Field(new Field("Table.HighwayID"))
  .Where( q => {
    if (HwyID > 0) {
        q.Where("Table.HighwayID", HwyID);
    }
  })
}

Allan

Chandler242

Hey Allan,

I was so absorbed to .Where() that I didn't even think of 'if'. Thank you for your patience and kindness.

Regards,

Yongqi