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PostgreSQL: Difference between text and varchar (character varying)
... article does detailed testing to show that the performance of inserts and selects for all 4 data types are similar. It also takes a detailed look at alternate ways on constraining the length when needed. Function based constraints or domains provide the advantage of instant increase of the length c...
Reading Excel files from C#
...ed Properties=Excel 8.0;", fileName);
var adapter = new OleDbDataAdapter("SELECT * FROM [workSheetNameHere$]", connectionString);
var ds = new DataSet();
adapter.Fill(ds, "anyNameHere");
DataTable data = ds.Tables["anyNameHere"];
This is what I usually use. It is a little different because I u...
Can Android Studio be used to run standard Java projects?
...id Studio. If you do not have one, create one.
Click File > New Module. Select Java Library and click Next.
Fill in the package name, etc and click Finish. You should now see a Java module inside your Android project.
Add your code to the Java module you've just created.
Click on the drop down to...
How to automatically install Emacs packages by specifying a list of package names?
...nsure keyword to install packages automatically. This also sets up package-selected-packages if you need to access the package list through customize or programatically.
– Nick McCurdy
Apr 21 '17 at 22:16
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MySQL INSERT INTO table VALUES.. vs INSERT INTO table SET
...statement insert rows based on explicitly specified values. The INSERT ... SELECT form inserts rows selected from another table or tables.
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SQL left join vs multiple tables on FROM line?
...nts that have employees, but always list all companies.
So you do this:
SELECT * -- for simplicity
FROM Company, Department, Employee
WHERE Company.ID *= Department.CompanyID
AND Department.ID = Employee.DepartmentID
Note that the last one there is an inner join, in order to fulfill the crite...
java.sql.SQLException: - ORA-01000: maximum open cursors exceeded
... a query, specifically the position where a reader is in a ResultSet. Each SELECT statement has a cursor, and PL/SQL stored procedures can open and use as many cursors as they require. You can find out more about cursors on Orafaq.
A database instance typically serves several different schemas, man...
How to change package name of an Android Application
...
Right-click on the package name (src/com.android.gesture.builder).
Select Refactor > Rename and change the name, for example to
com.android.gestureNEW.builder.
Open the manifest file. Inside the
<manifest> tag, change the package name to
com.android.gestureNEW.builder.
...
jQuery selector for inputs with square brackets in the name attribute
I'm trying to select this element which has square brackets in the name attribute:
5 Answers
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Getting Checkbox Value in ASP.NET MVC 4
... the value on the checkbox element to false. This means that when you then select the checkbox, you are posting the value "false" with the form. When you don't select it, it doesn't get posted, so the model defaults to false. Which is why you are seeing a false value in both cases.
The value is onl...