SQL check blank cells

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Hello!

I try to read out from a GDB, this way:

C#

string sql = "select * from test where start > '2011.04.22. 00:00:00'"

But there are a lot of blank cells, because they aren't started yet. I want these cells to be listed. How can I check it?

Edit:
Image:http://img198.imageshack.us/img198/4467/testvw.png[^]

Posted 25-Apr-11 20:17pm

velvet7

Updated 25-Apr-11 20:24pm

m@dhu

v3

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ZeeroC00l 26-Apr-11 2:20am

What you mean by lot of blank cells ??
can you post an example of how your table looks like with a few data inserted into it.?

velvet7 26-Apr-11 2:26am

Image above.

2 solutions

Solution 2

The comments were growing too long to keep track of, so I am posting this as an answer instead.

Can you please, post the create table SQL of the particular table you are talking about, well, if the table got around 100+ fields, omit other fields. And also, tell us what is the database engine that you are using? GDB is for what kind of database?

Regards

Posted 26-Apr-11 7:30am

CodeHawkz

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Abhinav S · Accepted Answer · 2011-04-25T20:21:00

Solution 1

Why don't you just check for nulls instead?
Or you could provide a default value into your table column.

Posted 25-Apr-11 20:21pm

Abhinav S

Comments

velvet7 26-Apr-11 2:24am

Actually the problem is this is not my database. It is generated by another program.
And the database doesn't allow NULL.

Sergey Alexandrovich Kryukov 26-Apr-11 2:27am

Does not allow Null? SQL?!
That's new to me. I'm not an expert, but did anyone heard about such stuff?

Thank you.
--SA

velvet7 26-Apr-11 2:31am

"I try to read out from a GDB".
I just need an SQL command.
Anyway, to be exact the field is set to "Not null".

CodeHawkz 26-Apr-11 2:34am

@SA: I think he meant, the fields in his table does not allow nulls.

@Abhinav: Why don't you try checking the length of the field after trimming? If it is zero, it should be the blank :) Just a thought

velvet7 26-Apr-11 2:38am

To answer to the question you asked from Abhinav: I would like to make the read time a bit shorter this way, because now it takes ~3 second (on my computer, and this will be used on a slower one!). So to check it, I have to read all cells.

CodeHawkz 26-Apr-11 4:54am

:) Oh.. How many records are we talking about here? 100000 at least? And what is the value of the blank cell? A space??

velvet7 26-Apr-11 9:00am

There are about a million records, and a space can't be a datetime, so I don't think.

ZeeroC00l 26-Apr-11 2:42am

I am not an expert but how can the cell be left blank when the cell is set to NOL NULL ?

CodeHawkz 26-Apr-11 4:52am

Blank = A space? :)

ZeeroC00l 26-Apr-11 9:14am

Well First of all, you can't assign space to everything. What if the field is a date/time field ? In that case spce wont be meaningless.

Hypothetically, say if your cell contains space, then you cant check for NULL in the where condition. And what if the number of space is more than 1 ? That would make things more complex

Sergey Alexandrovich Kryukov 26-Apr-11 11:30am

How they don't allow null? It's weird.
--SA

Abhinav S 26-Apr-11 2:30am

Try checking for nulls in your query.

Sergey Alexandrovich Kryukov 26-Apr-11 2:25am

This is correct, a 5.
--SA

Abhinav S 26-Apr-11 2:29am

Thank you.