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Rails: How can I set default values in ActiveRecord?
...
See Paul Russell's comment on this answer for more details
If you're only selecting a subset of columns for a model (ie; using select in a query like Person.select(:firstname, :lastname).all) you will get a MissingAttributeError if your init method accesses a column that hasn't been included in the...
Binding an enum to a WinForms combo box, and then setting it
...s.DataSource = Enum.GetValues(typeof(Status));
Getting the enum from the selected item
Status status;
Enum.TryParse<Status>(cbStatus.SelectedValue.ToString(), out status);
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improv...
Favourite performance tuning tricks [closed]
...n-optimal query plan
Break up the Join
Can you break up the join?
Pre-select foreign keys into a temporary table
Do half the join and put results in a temporary table
Are you using the right kind of temporary table?
#temp tables may perform much better than @table variables with large volum...
DBMS_OUTPUT.PUT_LINE not printing
...tion i want it to (firstName, lastName) and then the other values from the select query in a table below.
6 Answers
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How can I view the shared preferences file using Android Studio?
...in. 4. Start Android Emulator (in my case API 24) 5. Launch stetho-sample (select it from run configuration menu next to green arrow 6. On your PC open latest Chrome browser 7. go by chrome://inspect address 8. chose your emulator in list. 9. In opened window go to Resources tab. 10. Find your share...
How to move the cursor word by word in the OS X Terminal
...e sequences for you:
Open Terminal preferences (cmd+,);
At Settings tab, select Keyboard and double-click ⌥ ← if it's there, or add it if it's not.
Set the modifier as desired, and type the shortcut key in the box: esc+B, generating the text \033b (you can't type this text manually).
Repeat fo...
'Java' is not recognized as an internal or external command
...
For Windows 7:
Right click on My Computer
Select Properties
Select Advanced System Settings
Select Advanced tab
Select Environment Variables
Select Path under System Variables
Click on Edit button
In Variable value editor paste this at the start of the line
C:\Progr...
facebook: permanent Page Access Token?
...ken.
1. Get User Short-Lived Access Token
Go to the Graph API Explorer.
Select the application you want to get the access token for (in the "Application" drop-down menu, not the "My Apps" menu).
Click "Get Token" > "Get User Access Token".
In the pop-up, under the "Extended Permissions" tab, c...
How to move child element from one parent to another using jQuery [duplicate]
...he actual id's of the fields had multiple -'s and _'s in it, and I was not selecting the element because the id wasn't matching. Thank you.
– Dom
Apr 8 '10 at 2:40
add a comme...
Delete sql rows where IDs do not have a match from another table
...HERE f.id IS NULL
Using NOT EXISTS:
DELETE FROM BLOB
WHERE NOT EXISTS(SELECT NULL
FROM FILES f
WHERE f.id = fileid)
Using NOT IN:
DELETE FROM BLOB
WHERE fileid NOT IN (SELECT f.id
FROM FILES f)
Warning
Whenever possible, per...