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Convert Rows to columns using 'Pivot' in SQL Server
...9, 3, 87);
If your values are known, then you will hard-code the query:
select *
from
(
select store, week, xCount
from yt
) src
pivot
(
sum(xcount)
for week in ([1], [2], [3])
) piv;
See SQL Demo
Then if you need to generate the week number dynamically, your code will be:
DECLARE @c...
Saving enum from select in Rails 4.1
...num.
I changed the input to be the following:
f.input :color, :as => :select, :collection => Wine.colors.keys.to_a
Which generated the following HTML:
<select id="wine_color" name="wine[color]">
<option value=""></option>
<option value="red">red</option>
...
How to Select Every Row Where Column Value is NOT Distinct
I need to run a select statement that returns all rows where the value of a column is not distinct (e.g. EmailAddress).
7 A...
MySQL INNER JOIN select only one row from second table
...have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL statements before so I want to know what i'm doing wrong. Appreciate the help
...
Fast way to discover the row count of a table in PostgreSQL
...in your case.
Instead of getting the exact count (slow with big tables):
SELECT count(*) AS exact_count FROM myschema.mytable;
You get a close estimate like this (extremely fast):
SELECT reltuples::bigint AS estimate FROM pg_class where relname='mytable';
How close the estimate is depends on ...
How to take MySQL database backup using MySQL Workbench?
...ble) within Server Administration.
Steps to Create New Server Instance:
Select New Server Instance option within Server Administrator.
Provide connection details.
After creating new server instance , it will be available in Server Administration list. Double click on Server instance you have cr...
UITableview: How to Disable Selection for Some Rows but Not Others
... able to click it at all) The table contains two groups. I want to disable selection for the first group only but not the second group. Clicking the first row of second group navigates to my tube player view .
...
What is the reason not to use select *?
...eople claim that you should specifically name each column you want in your select query.
20 Answers
...
SQL Server SELECT into existing table
I am trying to select some fields from one table and insert them into an existing table from a stored procedure. Here is what I am trying:
...
How do SQL EXISTS statements work?
... criteria -- this is why it can be faster than IN. Also be aware that the SELECT clause in an EXISTS is ignored - IE:
SELECT s.*
FROM SUPPLIERS s
WHERE EXISTS (SELECT 1/0
FROM ORDERS o
WHERE o.supplier_id = s.supplier_id)
...should hit a division by zero error...