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What should every developer know about databases? [closed]
...fluence that choice;
The concept of coverage (why you shouldn't just write SELECT *);
The difference between a clustered and non-clustered index;
Why more/bigger indexes are not necessarily better;
Why you should try to avoid wrapping filter columns in functions.
Designers should also be aware of ...
MySql: Tinyint (2) vs tinyint(1) - what is the difference?
...rows affected (0.02 sec)
Records: 3 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM tin3;
+----+------------+
| id | val |
+----+------------+
| 1 | 0000000012 |
| 2 | 0000000007 |
| 4 | 0000000101 |
+----+------------+
3 rows in set (0.00 sec)
mysql>
mysql> SELECT LENGTH(val)...
How can I get all constants of a type by reflection?
...mp;& !fi.IsInitOnly && fi.FieldType == typeof(T))
.Select(x => (T)x.GetRawConstantValue())
.ToList();
}
}
Then for a class like this
static class MyFruitKeys
{
public const string Apple = "apple";
public const string Plum = "plum";
public con...
How to programmatically send SMS on the iPhone?
...t with predefined (prefill) body text. Thos body text should be the manual selection from 4 possible options. E.g. The app opens and pop-ups "select reason". Then 4 options are available. Next the user selects one of these 4 options and then an automatic SMS is sent having as body text the choice of...
Maximum number of records in a MySQL database table
...g with multiple billions of entries? (which would probably just make your select statements melt down long before then)
– Kzqai
Apr 26 '10 at 19:35
2
...
How exactly does work?
...ere are up to date. I was addressing the fact that the wrong answer wasn't selected at the time the question was asked. Perhaps you should police the folks spreading false assessments about the community improperly selecting answers, instead of folks trying to remind people that things change over ...
Index (zero based) must be greater than or equal to zero
...care.
//Wrong Code:
string name="my name";
string age=25;
String.Format(@"Select * from table where name='{1}' and age={1}" +name, age);
//Right Code:
string name="my name";
string age=25;
String.Format(@"Select * from table where name='{1}' and age={1}" , name, age);
...
How to move columns in a MySQL table?
...min provides a GUI for this within the structure view of a table.
Check to select the column you want to move and click the change action at the bottom of the column list.
You can then change all of the column properties and you'll find the 'move column' function at the far right of the screen.
Of ...
One Activity and all other Fragments [closed]
...I used the single Activity approach and a Facebook style navigation. When selecting items from the navigation list I update a single Fragment container to display that section.
That said, having a single Activity also introduces a lot of complexities. Let's say you have an edit form, and for so...
Maven: Command to update repository after adding dependency to POM
...:
Right click on the project ->Run As -- >Run configurations.
Then select mavenBuild.
Then click new button to create a configuration of the selected
type .Click on Browse workspace then select your project and in
goals specify eclipse:eclipse
You can refer to how to run the command mvn e...