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Android: how to make keyboard enter button say “Search” and handle its click?
...out. Some apps have a EditText (textbox) which, when you touch it and it brings up the on-screen keyboard, the keyboard has a "Search" button instead of an enter key.
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How do servlets work? Instantiation, sessions, shared variables and multithreading
Suppose, I have a webserver which holds numerous servlets. For information passing among those servlets I am setting session and instance variables.
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When to use Comparable and Comparator
I have a list of objects I need to sort on a field, say Score. Without giving much thought I wrote a new class that implements Comparator, that does the task and it works.
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JSON.NET Error Self referencing loop detected for type
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Fix 1: Ignoring circular reference globally
(I have chosen/tried this one, as have many others)
The json.net serializer has an option to ignore circular references. Put the following code in WebApiConfig.cs file:
config.Formatters.JsonF...
Foreign Key to non-primary key
I have a table which holds data, and one of those rows needs to exist in another table. So, I want a foreign key to maintain referential integrity.
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MySql Table Insert if not exist otherwise update
It works if the datenum exists, but I want to insert this data as a new row if the datenum does not exist.
3 Answers
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'IF' in 'SELECT' statement - choose output value based on column values
...unctions.html.
Additionally, you could handle when the condition is null. In the case of a null amount:
SELECT id,
IF(type = 'P', IFNULL(amount,0), IFNULL(amount,0) * -1) as amount
FROM report
The part IFNULL(amount,0) means when amount is not null return amount else return 0.
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Get size of all tables in database
I have inherited a fairly large SQL Server database. It seems to take up more space than I would expect, given the data it contains.
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How should equals and hashcode be implemented when using JPA and Hibernate
How should model class's equals and hashcode be implemented in Hibernate? What are the common pitfalls? Is the default implementation good enough for most cases? Is there any sense to use business keys?
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How to check if a stored procedure exists before creating it
...time a client executes the "database management" functionality. The script includes creating stored procedures on the client database. Some of these clients might already have the stored procedure upon running the script, and some may not. I need to have the missing stored procedures added to the c...