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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...int, unique key (u));
mysql> insert into foo (u) values (10);
mysql> select * from foo;
+----+------+
| id | u |
+----+------+
| 1 | 10 |
+----+------+
mysql> show create table foo\G
CREATE TABLE `foo` (
`id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
`u` int(11) DEFAULT NULL,
...
Python Pandas merge only certain columns
...
You can use .loc to select the specific columns with all rows and then pull that. An example is below:
pandas.merge(dataframe1, dataframe2.iloc[:, [0:5]], how='left', on='key')
In this example, you are merging dataframe1 and dataframe2. You h...
Error: CUICatalog: Invalid asset name supplied: (null), or invalid scale factor : 2.000000
...
In Xcode 6.4, this seems to occur when using "Selected Image" for a tab bar item in the storyboard, even if it's a valid image.
This doesn't actually seem to set the selected state image anyway, so it needs to be defined in User Defined Runtime Attributes, and removed...
Hibernate JPA Sequence (non-Id)
... an entity which has defined generated properties, it immediately issues a select afterwards to retrieve the generated values."
For properties generated on insert only, your property mapping (.hbm.xml) would look like:
<property name="foo" generated="insert"/>
For properties generated on i...
How to get TimeZone from android mobile?
...ndar.getInstance();
TimeZone tz = cal.getTimeZone();
It will return user selected timezone.
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Centering controls within a form in .NET (Winforms)? [duplicate]
...on't care about resizing (if you do care, go with Mitch Wheats solution):
Select the control -> Format (menu option) -> Center in Window -> Horizontally or Vertically
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How to simulate a button click using code?
...mes be a better choice in my experience than performClick(). If a user has selection sounds enabled, then performClick() could cause the user to hear two continuous selection sounds that are somewhat layered on top of each other which can be jarring. (One selection sound for the user's first button ...
C# switch statement limitations - why?
...values of switch labels are distinct (so that only one switch block can be selected for a given switch-expression)
Consider this code example in the hypothetical case that non-constant case values were allowed:
void DoIt()
{
String foo = "bar";
Switch(foo, foo);
}
void Switch(String val1...
Hiding the scroll bar on an HTML page
... /* 7 */
These can each be combined with additional pseudo-selectors:
:horizontal – The horizontal pseudo-class applies to any scrollbar pieces that have a horizontal orientation.
:vertical – The vertical pseudo-class applies to any scrollbar pieces that have a vertical orienta...
If table exists drop table then create it, if it does not exist just create it
...up the old table,
obviously.
Wrapping all statements with something like SELECT GET_LOCK('__upgrade', -1); ... DO RELEASE_LOCK('__upgrade'); allows to just invoke all statements sequentially without error checking, but I don't think it's a good idea: complexity increases and locking functions in M...