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What is causing this ActiveRecord::ReadOnlyRecord error?
...s automatically inferred only if :joins was specified without an explicit :select nor an explicit (or finder-scope-inherited) :readonly option (see the implementation of set_readonly_option! in active_record/base.rb for Rails 2.3.4, or the implementation of to_a in active_record/relation.rb and of c...
How to avoid the “divide by zero” error in SQL?
...rder to avoid a "Division by zero" error we have programmed it like this:
Select Case when divisor=0 then null
Else dividend / divisor
End ,,,
But here is a much nicer way of doing it:
Select dividend / NULLIF(divisor, 0) ...
Now the only problem is to remember the NullIf bit, if I use the "/"...
Android: How to bind spinner to custom object list?
... has its own ID (the IDs are not equal to display sequence). When the user selects the name from the list the variable currentID has to be changed.
...
How to get last inserted id?
...
INSERT INTO aspnet_GameProfiles(UserId,GameId)
VALUES(@UserId, @GameId);
SELECT SCOPE_IDENTITY()
And then
Int32 newId = (Int32) myCommand.ExecuteScalar();
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How do I show the value of a #define at compile-time?
...ment with the argument enclosed in double quotes. Thus:
#define STR(x) #x
char *s1 = "abc";
char *s2 = STR(abc);
will assign identical values to s1 and s2. If you run gcc -E you can see this in the output. Perhaps STR would be better named something like ENQUOTE.
This solves the problem of putti...
Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
...n multiple courses, books, and jobs, I have seen text fields defined as VARCHAR(255) as kind of the default for "shortish" text. Is there any good reason that a length of 255 is chosen so often, other than being a nice round number ? Is it a holdout from some time in the past when there was a goo...
How can I get the list of a columns in a table for a SQLite database?
...(first_name varchar, last_name varchar, email_address varchar);
sqlite> select * from sqlite_master;
table|people|people|2|CREATE TABLE people (first_name varchar, last_name varchar, email_address varchar)
To get column information you can use the pragma table_info(table_name) statement:
sqlit...
For loop for HTMLCollection elements
... capability works in Edge 41.16299.15.0 for a nodeList as in document.querySelectorAll(), but not an HTMLCollection as in document.getElementsByClassName() so you have to manually assign the iterator to use it in Edge for an HTMLCollection. It is a total mystery why they'd fix one collection type, ...
How to resume Fragment from BackStack if exists
...teName);
ft.commit();
}
}
The conditional was changed a bit since selecting the same fragment while it was visible also caused duplicate entries.
Implementation:
I highly suggest not taking the the updated replaceFragment() method apart like you did in your code. All the logic is containe...
Android: Coloring part of a string using TextView.setText()?
...eSpan(android.graphics.Typeface.BOLD);
// Set the text color for first 4 characters
sb.setSpan(fcs, 0, 4, Spannable.SPAN_INCLUSIVE_INCLUSIVE);
// make them also bold
sb.setSpan(bss, 0, 4, Spannable.SPAN_INCLUSIVE_INCLUSIVE);
yourTextView.setText(sb);
...