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How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
...t have to have a placeholder for it in the Insert statement. Then a simple select * into the target table auto populated this column. Here are the two SQL statements that I used on PostgreSQL 9.6.4.
ALTER TABLE target ADD COLUMN some_column SERIAL;
INSERT INTO target SELECT * from source;
...
Postgres: “ERROR: cached plan must not change result type”
...ng this error.
My application opened a database connection and prepared a SELECT statement for execution.
Meanwhile, another script was modifying the database table, changing the data type of one of the columns being returned in the above SELECT statement.
I resolved this by restarting the applic...
Facebook database design?
...O_INCREMENT=2 DEFAULT CHARSET=utf8;
Friends of Friends Query:
(
select friend_id
from friends
where user_id = 1
) union (
select distinct ff.friend_id
from
friends f
join friends ff on ff.user_id = f.friend_id
where f.use...
Why would you use Expression rather than Func?
...y. Ie. you need database.data.Where(i => i.Id > 0) to be executed as SELECT FROM [data] WHERE [id] > 0. If you just pass in a Func, you've put blinders on your driver and all it can do is SELECT * and then once it's loaded all of that data into memory, iterate through each and filter out ev...
Enabling auto layout in iOS 6 while remaining backwards compatible with iOS 5
...tolayout can be enabled or disabled on each .storyboard or .xib file. Just select the particular file and modify the "Use Autolayout" property using the File inspector in Xcode:
Using autolayout enabled interface files with the deployment target set to an iOS version prior to 6.0 results in compi...
SQL update trigger only when column is modified
...dDate, ModifiedUser, ModifiedHost, QtyToRepairOld, QtyToRepairNew)
SELECT S.OrderNo, S.PartNumber, GETDATE(), SUSER_NAME(), HOST_NAME(), D.QtyToRepair, I.QtyToRepair FROM SCHEDULE S
INNER JOIN Inserted I ON S.OrderNo = I.OrderNo and S.PartNumber = I.PartNumber
INNER JOIN Dele...
Turn off constraints temporarily (MS SQL)
...8)
-- List of all tables
DECLARE triggerCursor CURSOR FOR
SELECT t.TABLE_NAME AS TableName
, t.TABLE_SCHEMA AS TableSchema
FROM INFORMATION_SCHEMA.TABLES t
ORDER BY t.TABLE_NAME, t.TABLE_SCHEMA
OPEN triggerCursor
FETCH NEXT FROM triggerC...
Handling a Menu Item Click Event - Android
...inflate(R.menu.game_menu, menu);
return true;
}
simple code for menu selected
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle item selection
switch (item.getItemId()) {
case R.id.new_game:
newGame();
return true;
case R.id.help:
...
How is the default submit button on an HTML form determined?
...cus for any visual element yet will still cause the invisible button to be selected. To avoid this issue, simply set tabindex attributes accordingly and omit a tabindex attribute on the invisible submit button. While it may seem out of place to promote these styles to !important, they should preven...
How to calculate time in hours between two dates in iOS
...developer.apple.com/library/mac/navigation/
or if you are using Xcode just select help/documentation from the menu.
See: how-to-convert-an-nstimeinterval-seconds-into-minutes
--edit: See ÐąrέÐέvil's answer below for correctly handling daylight savings/leap seconds
...