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Rails auto-assigning id that already exists
...mpany.id column to the highest value in the table with a query like this:
SELECT setval('company_id_seq', (SELECT max(id) FROM company));
I am guessing at your sequence name "company_id_seq", table name "company", and column name "id" ... please replace them with the correct ones. You can get the...
What are Unwind segues for and how do you use them?
...e want to unwind to Red from Green when the button is pressed:
You must select the action which is defined in the view controller you want to unwind to:
You can also unwind to Red from Blue (which is "two steps away" in the navigation stack). The key is selecting the correct unwind action.
Be...
How to add 'ON DELETE CASCADE' in ALTER TABLE statement
...ARE
CURSOR consCols (theCons VARCHAR2, theOwner VARCHAR2) IS
select * from user_cons_columns
where constraint_name = theCons and owner = theOwner
order by position;
firstCol BOOLEAN := TRUE;
begin
-- For each constraint
FOR cons IN (sel...
How do I use FileSystemObject in VBA?
...crrun.dll
To reference this file, load the
Visual Basic Editor (ALT+F11)
Select Tools > References from the drop-down menu
A listbox of available references will be displayed
Tick the check-box next to 'Microsoft Scripting Runtime'
The full name and path of the scrrun.dll file will be displayed...
How to select the rows with maximum values in each group with dplyr? [duplicate]
I would like to select a row with maximum value in each group with dplyr.
6 Answers
6
...
Difference between a theta join, equijoin and natural join
...ed SQL query would be like this (you can play with all the examples here)
SELECT *
FROM Product
JOIN Component
ON Product.Pname = Component.Pname
and the result:
| PNAME | PRICE | CNAME | COST |
----------------------------------
| Laptop | 1500 | CPU | 500 |
| Laptop | 1500 | hdd ...
right click context menu for datagridview
...d like to rightclick on a row and have a menu pop up. Then i would like to select things such as copy, validate, etc
7 Answ...
How can I clone an SQL Server database on the same server in SQL Server 2008 Express?
...is optional.
Click to clone database and open restore dialog (see image)
Select Device and add the backup file from step 3.
Change destination to test database
Change location of database files, it must be different from the original. You can type directly into text box, just add postfix. (NOTE:...
How do you return the column names of a table?
...
Not sure if there is an easier way in 2008 version.
USE [Database Name]
SELECT COLUMN_NAME,*
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'YourTableName' AND TABLE_SCHEMA='YourSchemaName'
share
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...
Pushing from local repository to GitHub hosted remote
... my GIT version 1.8.4:
From the local repository folder, right click and select 'Git Commit Tool'.
There, select the files you want to upload, under 'Unstaged Changes' and click 'Stage Changed' button. (You can initially click on 'Rescan' button to check what files are modified and not uploaded ye...