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Ruby on Rails form_for select field with class
I am beating my head against the wall on this one. I want to make a simple select tag using the f.select tag but nothing I do works. I put an example below:
...
Modifying a subset of rows in a pandas dataframe
...The df.A==0 expression creates a boolean series that indexes the rows, 'B' selects the column. You can also use this to transform a subset of a column, e.g.:
df.loc[df.A==0, 'B'] = df.loc[df.A==0, 'B'] / 2
I don't know enough about pandas internals to know exactly why that works, but the basic is...
Selecting last element in JavaScript array [duplicate]
...gth less 1.
Mozilla Docs on Slice
Performance of the various methods for selecting last array element
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How can i query for null values in entity framework?
...try in table
where entry.something.Equals(value)
select entry;
Workaround for Linq-to-Entities (ouch!):
var result = from entry in table
where (value == null ? entry.something == null : entry.something == value)
select entry;
This is a nasty b...
Accessing an SQLite Database in Swift
...pared statement: \(errmsg)")
}
statement = nil
Prepare new statement for selecting values from table and loop through retrieving the values:
if sqlite3_prepare_v2(db, "select id, name from test", -1, &statement, nil) != SQLITE_OK {
let errmsg = String(cString: sqlite3_errmsg(db)!)
pri...
Stash only one file out of multiple files that have changed with Git?
...
You can also use git stash save -p "my commit message". This way you can select which hunks should be added to stash, whole files can be selected as well.
You'll be prompted with a few actions for each hunk:
y - stash this hunk
n - do not stash this hunk
q - quit; do not stash this hun...
Proper way to rename solution (and directories) in Visual Studio
...story of the file. For example, with TortoiseSVN, right click on the file, select TortoiseSVN .. Rename.
In the .sln file, edit all instances of Project1 to be Project2, using a text editor like NotePad.
Restart Visual Studio, and everything will work as before, but with the project in a different ...
Cleanest way to build an SQL string in Java
...uild an SQL string to do database manipulation (updates, deletes, inserts, selects, that sort of thing) - instead of the awful string concat method using millions of "+"'s and quotes which is unreadable at best - there must be a better way.
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How to split a string literal across multiple lines in C / Objective-C?
...de it.
#define QUOTE(...) #__VA_ARGS__
const char *sql_query = QUOTE(
SELECT word_id
FROM table1, table2
WHERE table2.word_id = table1.word_id
ORDER BY table1.word ASC
);
the preprocessor turns this into:
const char *sql_query = "SELECT word_id FROM table1, table2 WHERE table2.wo...
Which timestamp type should I choose in a PostgreSQL database?
...al time zone
test=> SET timezone = 'America/Los_Angeles';
SET
test=> SELECT NOW();
now
-------------------------------
2011-05-27 15:47:58.138995-07
(1 row)
test=> SELECT NOW() AT TIME ZONE 'UTC';
timezone
----------------------------
2011-...