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Insert Update stored proc on SQL Server
...re the check for existence
should only be done when there is a
very valid reason to justify the
additional I/O. The optimized way to
do things is to make sure that you
have little reads as possible on the
DB.
The best strategy is to attempt the
update. If no rows are affected by t...
How do I join two lines in vi?
...u join lines as is -- without adding or removing whitespaces:
S<Switch_ID>_F<File type>
_ID<ID number>_T<date+time>_O<Original File name>.DAT
Result:
S<Switch_ID>_F<File type>_ID<ID number>_T<date+time>_O<Original File name>.DAT
With ...
What does inverse_of do? What SQL does it generate?
...the documentation, it seems like the :inverse_of option is a method for avoiding SQL queries, not generating them. It's a hint to ActiveRecord to use already loaded data instead of fetching it again through a relationship.
Their example:
class Dungeon < ActiveRecord::Base
has_many :traps, :in...
SQL Server : Columns to Rows
...You can use the UNPIVOT function to convert the columns into rows:
select id, entityId,
indicatorname,
indicatorvalue
from yourtable
unpivot
(
indicatorvalue
for indicatorname in (Indicator1, Indicator2, Indicator3)
) unpiv;
Note, the datatypes of the columns you are unpivoting must be th...
How to create a checkbox with a clickable label?
...
Method 2: Use the for Attribute
Use the for attribute (match the checkbox id):
<input type="checkbox" name="checkbox" id="checkbox_id" value="value">
<label for="checkbox_id">Text</label>
NOTE: ID must be unique on the page!
Explanation
Since the other answers don't mention it, a...
How can I make a JPA OneToOne relation lazy
...be lazy.
Replacing one-to-one with one-to-many is pretty much never a good idea. You can replace it with unique many-to-one but there are other (possibly better) options.
Rob H. has a valid point, however you may not be able to implement it depending on your model (e.g. if your one-to-one associat...
Scrollview vertical and horizontal in android
...d solution:
Custom ScrollView:
package com.scrollable.view;
import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.ScrollView;
public class VScroll extends ScrollView {
public VScroll(Context context, AttributeSet attrs, int ...
How to disable/enable select field using jQuery?
...ould like to use code like this:
<form>
<input type="checkbox" id="pizza" name="pizza" value="yes">
<label for="pizza">I would like to order a</label>
<select id="pizza_kind" name="pizza_kind">
<option>(choose one)</option>
<option value="m...
Postgresql aggregate array
...
Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1
SELECT s.name, array_agg(g.Mark) as marks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need to repeat the columns...
How can I SELECT rows with MAX(Column value), DISTINCT by another column in SQL?
...
@Young the problem with your query is that it may return id, player and resource of non-max row for a given home i.e. for home = 10 you may get : 3 | 10 | 04/03/2009 | john | 300 In other words it doesn't guarantees that all column of a row in resultset will belong to max(da...