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Replacing NULL with 0 in a SQL server query
...u want to replace a possibly null column with something else, use IsNull.
SELECT ISNULL(myColumn, 0 ) FROM myTable
This will put a 0 in myColumn if it is null in the first place.
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Get the last inserted row ID (with SQL statement) [duplicate]
...alue using:
INSERT INTO dbo.YourTable(columns....)
VALUES(..........)
SELECT SCOPE_IDENTITY()
This works as long as you haven't inserted another row - it just returns the last IDENTITY value handed out in this scope here.
There are at least two more options - @@IDENTITY and IDENT_CURRENT - r...
How to debug a single thread in Visual Studio?
...most correct and usable way is to:
Hit Ctrl+A in the breakpoints window (select all breakpoints).
Right click and select "Filter...".
Enter "ThreadId=(current thread id)".
In Visual Studio 2015 and newer, the process is similar:
Hit Ctrl+A in the breakpoints window (select all breakpoints).
Ri...
MySQL indexes - what are the best practices?
...t them. Generally I put an index on any fields that I will be searching or selecting using a WHERE clause but sometimes it doesn't seem so black and white.
...
How do I select the parent form based on which submit button is clicked?
...
You can select the form like this:
$("#submit").click(function(){
var form = $(this).parents('form:first');
...
});
However, it is generally better to attach the event to the submit event of the form itself, as it will tri...
Android file chooser [closed]
...ent in an Intent.createChooser() like this:
private static final int FILE_SELECT_CODE = 0;
private void showFileChooser() {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("*/*");
intent.addCategory(Intent.CATEGORY_OPENABLE);
try {
startActivityForR...
Psql list all tables
...This is where the INFORMATION_SCHEMA comes to the rescue. To list tables:
SELECT table_name FROM information_schema.tables WHERE table_schema = 'public';
BTW, if you ever want to see what psql is doing in response to a backslash command, run psql with the -E flag. eg:
$ psql -E regress
regre...
jQuery select all except first
In jQuery how do I use a selector to access all but the first of an element? So in the following code only the second and third element would be accessed. I know I can access them manually but there could be any number of elements so thats not possible. Thanks.
...
How can I return pivot table output in MySQL?
...OUP BY.
The basic SQL providing this pivot can look something like this:
SELECT P.`company_name`,
COUNT(
CASE
WHEN P.`action`='EMAIL'
THEN 1
ELSE NULL
END
) AS 'EMAIL',
COUNT(
CASE
WHEN P.`action`='PRINT' AND...
ReactJS Two components communicating
...te is also increasing in complexity, as we need to
manage active routes, selected tabs, spinners, pagination controls,
and so on.
Managing this ever-changing state is hard. If a model can update
another model, then a view can update a model, which updates another
model, and this, in tur...