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find vs find_by vs where
...is used as a helper when you're searching for information within a column, and it maps to such with naming conventions. For instance, if you have a column named name in your database, you'd use the following syntax:
Model.find_by(name: "Bob")
.where is more of a catch all that lets you use a bit...
Which SQL query is faster? Filter on Join criteria or Where clause?
...
Performance-wise, they are the same (and produce the same plans)
Logically, you should make the operation that still has sense if you replace INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
...
Sending email in .NET through Gmail
...ame");
var toAddress = new MailAddress("to@example.com", "To Name");
const string fromPassword = "fromPassword";
const string subject = "Subject";
const string body = "Body";
var smtp = new SmtpClient
{
Host = "smtp.gmail.com",
Port = 587,
EnableSsl = true,
DeliveryMethod = SmtpDeli...
GraphViz - How to connect subgraphs?
...the cluster's built-in "label" attribute, which should be set to the empty string (in Python, label='""'). This means I'm no longer adding edges that connect clusters directly, but it works in my particular situation.
share...
ssh “permissions are too open” error
...uldn't save any kind of file on the disk anymore.
I had to reboot OSX lion and reset the permissions on files and acls.
27 ...
How do I get the directory from a file's full path?
...are working with a FileInfo object, then there is an easy way to extract a string representation of the directory's full path via the DirectoryName property.
Description of the FileInfo.DirectoryName Property via MSDN:
Gets a string representing the directory's full path.
Sample usage:
stri...
Draw text in OpenGL ES
...aceView. This is slow and bad, but the most direct approach.
Render common strings to textures, and simply draw those textures. This is by far the simplest and fastest, but the least flexible.
Roll-your-own text rendering code based on a sprite. Probably second best choice if 2 isn't an option. A go...
Change Activity's theme programmatically
...ences pref = PreferenceManager
.getDefaultSharedPreferences(this);
String themeName = pref.getString("prefSyncFrequency3", "Theme1");
if (themeName.equals("Africa")) {
setTheme(R.style.AppTheme);
} else if (themeName.equals("Colorful Beach")) {
//Toast.makeText(this, "set theme", ...
Mongoose — Force collection name
...
This should do it
var UserInfo = new Schema({
username : String,
password : String
}, { collection: 'userinfo' });
See this link from the Mongoose documentation for more information.
share
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“Insert if not exists” statement in SQLite
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If you have a table called memos that has two columns id and text you should be able to do like this:
INSERT INTO memos(id,text)
SELECT 5, 'text to insert'
WHERE NOT EXISTS(SELECT 1 FROM memos WHERE id = 5 AND text = 'text to insert');
If a record already contains a row where ...