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Is this correct? [message #8577]

Mon, 19 March 2007 21:00

MikeyV
Messages: 20
Registered: February 2007

Promising Member

Is this the correct way to use SqlSum?

SQL * Select(SqlSum(PS)).From(AreaMission);

I get garbage in SQL[0]

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Re: Is this correct? [message #8579 is a reply to message #8577]

Tue, 20 March 2007 00:22

mirek
Messages: 13975
Registered: November 2005

Ultimate Member

Did you SQL.Fetch()?

There is also shorter form using operator%:

x = SQL % Select(SqlSum(PS)).From(AreaMission);

Mirek

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Re: Is this correct? [message #8581 is a reply to message #8577]

Tue, 20 March 2007 01:44

MikeyV
Messages: 20
Registered: February 2007

Promising Member

Quote:

Did you SQL.Fetch()?

No, I wasn't sure how. Is it like:

SQL * Select(SqlSum(PS)).From(AreaMission);
while(SQL.Fetch())
    x += SQL[0];

I also didn't realize that those were operators (ie. *, %, &) and I don't really know what they do. I will study the SQL header file and try to figure out what they do.

I will use that short form.

Thanks (again) Mirek!

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Re: Is this correct? [message #8585 is a reply to message #8579]

Tue, 20 March 2007 08:26

unodgs
Messages: 1366
Registered: November 2005
Location: Poland

Ultimate Contributor

luzr wrote on Mon, 19 March 2007 19:22

Did you SQL.Fetch()?

There is also shorter form using operator%:

x = SQL % Select(SqlSum(PS)).From(AreaMission);

Mirek

WOW! That's something new.

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Re: Is this correct? [message #8586 is a reply to message #8581]

Tue, 20 March 2007 10:12

mirek
Messages: 13975
Registered: November 2005

Ultimate Member

MikeyV wrote on Mon, 19 March 2007 20:44

Quote:

Did you SQL.Fetch()?

No, I wasn't sure how. Is it like:

SQL * Select(SqlSum(PS)).From(AreaMission);
while(SQL.Fetch())
    x += SQL[0];

Yes

Sure, we still owe everybody the nice SQL tutorial...

BTW, while above code is OK, I do not recommend using SQL with Fetch - it is global variable and way too often you can make a mistake here (by issuing another query on the same SQL).

So if you are going to Fetch, rather use:

Sql sql;
sql * Select(...
while(sql.Fetch())

Mirek

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