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postgresql return 0 if returned value is null
...LESCE(value [, ...])
The COALESCE function returns the first of its argu<em>mem>ents that is not null.
Null is returned only if all argu<em>mem>ents are null. It is often
used to substitute a default value for null values when data is
retrieved for display.
Edit
Here's an exa<em>mem>ple of COALESCE with your qu...
How do I add a ToolTip to a control?
I have so<em>mem>e controls that I would like to display a ToolTip for when the <em>mem>ouse is hovering over it. How can I do this? I would like to know how to do this properly in code, but also in the designer (There is a ToolTip co<em>mem>ponent in the toolbox, but I don't quite.. get it).
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What are the differences between vector and list data types in R?
What are the <em>mem>ain differences between vector and list data types in R? What are the advantages or disadvantages of using (or not) these two data types?
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What is the difference between trie and radix trie data structures?
Are the trie and radix trie data structures the sa<em>mem>e thing?
3 Answers
3
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List files co<em>mem><em>mem>itted for a revision
How do I list the file na<em>mem>es/paths that are co<em>mem><em>mem>itted, using a revision nu<em>mem>ber?
3 Answers
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How to correctly close a feature branch in <em>Mem>ercurial?
I've finished working on a feature branch feature-x . I want to <em>mem>erge results back to the default branch and close feature-x in order to get rid of it in the output of hg branches .
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What's the equivalent for eclipse's ALT+UP/DOWN (<em>mem>ove line) in Visual Studio?
In Eclipse, selecting a line and pressing Alt + ↑ / ↓ will <em>mem>ove the line up and down, a quick way to avoid copy&a<em>mem>p;paste.
Is there an equivalent in Visual Studio?
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HT<em>Mem>L/Javascript change div content
I have si<em>mem>ple HT<em>Mem>L code with so<em>mem>e javascript, it looks like:
6 Answers
6
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Best way to test if a generic type is a string? (C#)
I have a generic class that should allow any type, pri<em>mem>itive or otherwise. The only proble<em>mem> with this is using default(T) . When you call default on a value type or a string, it initializes it to a reasonable value (such as e<em>mem>pty string). When you call default(T) on an object, it returns null. Fo...
Which is better, return “<em>Mem>odelAndView” or “String” on spring3 controller
The way of return <em>Mem>odelAndView
2 Answers
2
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