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How to test an SQL Update statement before running it?
...yway) you can also do a sanity check which rows are affected by running a select using the same WHERE clause as the UPDATE.
So if you UPDATE is
UPDATE foo
SET bar = 42
WHERE col1 = 1
AND col2 = 'foobar';
The following will show you which rows will be updated:
SELECT *
FROM foo
WHERE col1 ...
NULL values inside NOT IN clause
...
Query A is the same as:
select 'true' where 3 = 1 or 3 = 2 or 3 = 3 or 3 = null
Since 3 = 3 is true, you get a result.
Query B is the same as:
select 'true' where 3 <> 1 and 3 <> 2 and 3 <> null
When ansi_nulls is on, 3 <&...
How to get the first and last date of the current year?
...
SELECT
DATEADD(yy, DATEDIFF(yy, 0, GETDATE()), 0) AS StartOfYear,
DATEADD(yy, DATEDIFF(yy, 0, GETDATE()) + 1, -1) AS EndOfYear
The above query gives a datetime value for midnight at the beginning of December 31. This ...
Open directory dialog
I want the user to select a directory where a file that I will then generate will be saved. I know that in WPF I should use the OpenFileDialog from Win32, but unfortunately the dialog requires file(s) to be selected - it stays open if I simply click OK without choosing one. I could "hack up" the f...
Visual Studio : short cut Key : Duplicate Line
...ure is now built-in in VS2017: Ctrl + E, V duplicates a line if nothing is selected, or duplicates selection. You can assign it to a different key combination, or find it in the menu:
See this reference for more information.
Pre VS2017, built-in method using clipboard
As @cand mentioned, you ca...
In JPA 2, using a CriteriaQuery, how to count results
...iaBuilder();
CriteriaQuery<Long> cq = qb.createQuery(Long.class);
cq.select(qb.count(cq.from(MyEntity.class)));
cq.where(/*your stuff*/);
return entityManager.createQuery(cq).getSingleResult();
Obviously you will want to build up your expression with whatever restrictions and groupings etc y...
Invalid postback or callback argument. Event validation is enabled using '
...
I had an experience with DataGrid. One of it's columns was "Select" button. When I was clicking "Select" button of any row I had received this error message:
"Invalid postback or callback argument. Event validation is enabled using in configuration or
<%@ Page EnableEve...
Setting JDK in Eclipse
...roperties the "JRE System Library" was still there. When I deleted it and selected "Use default Workspace JRE" only then did it pick up my change. I would have thought Eclipse should have updated my projects JRE when I selected a different JRE for my workspace
– MayoMan
...
MySQL Data - Best way to implement paging?
...e LIMIT clause can be used to constrain the number of rows returned by the SELECT statement. LIMIT takes one or two numeric arguments, which must both be nonnegative integer constants (except when using prepared statements).
With two arguments, the first argument specifies the offset of the first ro...
How to display default text “--Select Team --” in combo box on pageload in WPF?
...ComboBox Name="MyComboBox"
IsEditable="True"
IsReadOnly="True"
Text="-- Select Team --" />
You'll obviously need to add your other options, but this is probably the simplest way to do it.
There is however one downside to this method which is while the text inside your combo box will not be ...