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Spring JPA selecting specific columns
...Spring JPA to perform all database operations. However I don't know how to select specific columns from a table in Spring JPA?
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Naming convention for unique constraint
...imary key doesn't get a sequence number since there can be only one. The 2-char alpha suffix meanings are:
PK: Primary Key
AK: Alternate Key
FK: Foreign Key
IX: IndeX
CK: ChecK
DF: DeFault
I generally want to group metadata/system catalog data by the controlling object rather than by object type...
Xcode stops working after set “xcode-select -switch”
...eloper directory, not the Xcode application bundle. Run this:
sudo xcode-select --switch /Applications/Xcode.app/Contents/Developer
With recent versions of Xcode, you can go to Xcode ➙ Preferences… ➙ Locations and pick one of the options for Command Line Tools to set the location.
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How to check if a column exists in a SQL Server table?
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SQL Server 2005 onwards:
IF EXISTS(SELECT 1 FROM sys.columns
WHERE Name = N'columnName'
AND Object_ID = Object_ID(N'schemaName.tableName'))
BEGIN
-- Column Exists
END
Martin Smith's version is shorter:
IF COL_LENGTH('schemaName.tabl...
How do I use jQuery's form.serialize but exclude empty fields
... looking over the jQuery docs and I think we can do this in one line using selectors:
$("#myForm :input[value!='']").serialize() // does the job!
Obviously #myForm gets the element with id "myForm" but what was less obvious to me at first was that the space character is needed between #myForm and...
How to include “zero” / “0” results in COUNT aggregate?
...n outer join for this (and you need to use person as the "driving" table)
SELECT person.person_id, COUNT(appointment.person_id) AS "number_of_appointments"
FROM person
LEFT JOIN appointment ON person.person_id = appointment.person_id
GROUP BY person.person_id;
The reason why this is working, i...
Is it possible to use Java 8 for Android development?
...ce
Click on the Android SDK Manager button which is located on the toolbar
Select Android SDK Build tools Rev. 19.1 and Android Support Library only. Un-select everything else and install these two packages.
If everything goes well, ADT will be up and running.
The installation of the following to...
SQL Server equivalent to Oracle's CREATE OR REPLACE VIEW
...y create or replace views or stored procedures as follows.
IF NOT EXISTS (SELECT * FROM sys.views WHERE object_id = OBJECT_ID(N'[dbo].[vw_myView]'))
EXEC sp_executesql N'CREATE VIEW [dbo].[vw_myView] AS SELECT ''This is a code stub which will be replaced by an Alter Statement'' as [code_stub]'
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How to automatically navigate to the current class in Intellij Idea Project Tool Window?
...expands to show the currently open class (or file), and this class becomes selected in the tree.
6 Answers
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What columns generally make good indexes?
...earching the results speedily from tables. So it is most important step to select which columns to be indexed. There are two major places where we can consider indexing: columns referenced in the WHERE clause and columns used in JOIN clauses. In short, such columns should be indexed against which yo...