Posts by Fabio Torres • 26 points
2 posts
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answers468
viewsQ: Error "Object reference not defined for an object instance."
I am developing a Windows service that installs normal, but every time the start, it accuses the following error: Pcservice Error on: 15/12/2016 10:53:13 Undefined object reference for an object…
c#asked Fabio Torres 26 -
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votes1
answer61
viewsA: Check if an option already exists not to repeat it
Try using this query: $sql = "SELECT DISTINCT `cor` FROM `produtos`";