Locate field with null value

Posted on 2002-04-28
Medium Priority
Last Modified: 2012-05-04
I am using interbase as database with delphi 5.
i am using TIBQuery

Now in a table one field contains Null
i want to use locate function locate this field where value is null. Its now working.

Do you have any suggestions


Question by:rajniyadav
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
  • 2
  • 2

Expert Comment

ID: 6976398
Hi rajniyadav,

select * from sometable
where some_field is NULL

Author Comment

ID: 6976820
i want to user
Query.Locate function
Through sql it is working but i want to user locate function.

Expert Comment

ID: 6976843
something like this?

  Query1.Locate('STR', NULL, []);

STR - name of field where can be NULL
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!


Author Comment

ID: 6976989
when i am doing this locate function returns false even though there is one record with null.
LVL 27

Accepted Solution

kretzschmar earned 300 total points
ID: 6977577
? maybe
as the values in the locate-method are internal variants you could try

Query1.Locate('STR', varNull, []); //or varEmpty

just a guess

meikl ;-)


Author Comment

ID: 6979294
kretzschmar that works but i have one more problem.

Since i have more than on fields value to locate can u tell how can i store those values in a variable and use it in locate function

i made one string variable even variant and stored all the fieldvalues seperated with commas in that but it is not locating the right record.
And if i directly give the value in hte locate function it does locates

Can u help in that.
LVL 27

Expert Comment

ID: 7213588
even not tested, but try

Query1.Locate('FIELD1;FIELD2;FIELD3;FIELD4', VarArrayOf([varNull,varNull,varNull,varNull]), []); //or varEmpty

seems i got no notification at april

thanks for the points

meikl ;-)

Featured Post

Free Tool: Path Explorer

An intuitive utility to help find the CSS path to UI elements on a webpage. These paths are used frequently in a variety of front-end development and QA automation tasks.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Introduction The parallel port is a very commonly known port, it was widely used to connect a printer to the PC, if you look at the back of your computer, for those who don't have newer computers, there will be a port with 25 pins and a small print…
Introduction Raise your hands if you were as upset with FireMonkey as I was when I discovered that there was no TListview.  I use TListView in almost all of my applications I've written, and I was not going to compromise by resorting to TStringGrid…
Add bar graphs to Access queries using Unicode block characters. Graphs appear on every record in the color you want. Give life to numbers. Hopes this gives you ideas on visualizing your data in new ways ~ Create a calculated field in a query: …
In this video, Percona Solution Engineer Dimitri Vanoverbeke discusses why you want to use at least three nodes in a database cluster. To discuss how Percona Consulting can help with your design and architecture needs for your database and infras…
Suggested Courses

800 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question