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Formatting help

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format text bold: [b]bold text[/b]
format text italic: [i]italic text[/i]
insert hyperlink: [link=http://example.com/]link text[/link] / [link]http://example.com/[/link]
set text color: [color=#rgb]colored text[/color]
font size: [size=small]small text[/size]; [size=large]large text[/size]
insert list: [list][*]list item[/list]
insert image: [img]http://example.com/image.jpg[/img]; left: [img=left]http://example.com/image.jpg[/img]; right: [img=right]http://example.com/image.jpg[/img]; thumbnail: [img=thumbnail]http://example.com/image.jpg[/img]; thumbnail left: [img=thumbnail-left]http://example.com/image.jpg[/img]; thumbnail right: [img=thumbnail-right]http://example.com/image.jpg[/img]
upload image: upload image ...
insert TeX code: [tex]TeX code[/tex]
insert code: [inlinecode]code[/inlinecode]; [code]code[/code]; [code=css]code[/code]; [code=html]code[/code]; [code=javascript]code[/code]; [code=perl]code[/code]; [code=php]code[/code]; [code=sql]code[/code]; [code=xml]code[/code]

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Message:

> Hi Joe,
> 
> > Base:
> > 	LEFT JOIN mlf2_read_entries AS rst ON rst.posting_id = ft.id AND [b]rst.user_id[/b] = 0
> > Modified:
> > 	LEFT JOIN mlf2_read_entries AS rst ON rst.posting_id = ft.id AND [b]IFNULL(rst.user_id, NULL)[/b] = 0
> > 
> > I've come across this before and it always seems bizarre, but it works.
> 
> This looks strange. In the first statement, [inlinecode]rst.user_id[/inlinecode] is compared with zero. It is like
> 
> [code=php]if (rst.user_id == 0) {
>  //do something
> }[/code]
> 
> In your modified statement, a second condition is added in front of the prior condition. However, the second one is [i]identical[/i] to the condition of the first statement.
> [code=php]if (rst.user_id == NULL) {
>   rst.user_id = NULL;
> }
> if (rst.user_id == 0) {
>  //do something
> }[/code]
> 
> I could have immediately understood that the following change would make an improvement (no further type-cast),
> 
> [code=php]if (rst.user_id == NULL) {
>   rst.user_id = -1;
> }[/code]
> 
> However, if such a simple change works, we should change the statements...
> 
> /Micha

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