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Add a column to a table, if it does not already exist
...onstruct by using the sys.columns table io sys.objects.
IF NOT EXISTS (
SELECT *
FROM sys.columns
WHERE object_id = OBJECT_ID(N'[dbo].[Person]')
AND name = 'ColumnName'
)
share
|
...
How make Eclipse/EGit recognize existing repository information after update?
...ositories" dialogue, under Search criteria, enter the workspace directory, select "Look for nested repositores", and hit Search:
Select the repositories you want to add and click OK
"Share" each of the projects again using "use or create repository"
Open you existing project in Eclipse's Projec...
Selecting an element in iFrame jQuery
...rame. All the elements in that loaded page have their tokenid-s. I need to select the elements by those tokenid-s. Means - I click on an element on the main page and select corresponding element in the page in the iFrame. With the help of jQuery I'm doing it in the following way:
...
What is the difference between HAVING and WHERE in SQL?
What is the difference between HAVING and WHERE in an SQL SELECT statement?
20 Answers
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SQL query to get all values a enum can have
...
If you want an array:
SELECT enum_range(NULL::myenum)
If you want a separate record for each item in the enum:
SELECT unnest(enum_range(NULL::myenum))
Additional Information
This solution works as expected even if your enum is not in the...
jQuery selector regular expressions
...d or regular expressions (not sure on the exact terminology) with a jQuery selector.
10 Answers
...
Database Design for Tagging
... to rebuilt every time a question has a tag added or removed. A query like select * from question q inner join question_has_tag qt where tag_id in (select tag_id from tags where (what we want) minus select tag_id from tags where (what we don't) should be fine and scale out assuming the right b-tree ...
PostgreSQL create table if not exists
..._mytable()
RETURNS void
LANGUAGE plpgsql AS
$func$
BEGIN
IF EXISTS (SELECT FROM pg_catalog.pg_tables
WHERE schemaname = 'myschema'
AND tablename = 'mytable') THEN
RAISE NOTICE 'Table myschema.mytable already exists.';
ELSE
CREATE TABLE myschema...
Dynamically select data frame columns using $ and a character value
...and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic subset of cols , nether of these work
...
SQL query for finding records where count > 1
...ers that have more than one payment per day with the same account number
SELECT
user_id ,
COUNT(*) count
FROM
PAYMENT
GROUP BY
account,
user_id ,
date
Having
COUNT(*) > 1
Update
If you want to only include those that have a distinct ZIP you can get a distinct set first and then perfor...