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Database development mistakes made by application developers [closed]
... the log output from Hibernate and you'll see all the queries begin with:
SELECT DISTINCT ...
This is a bit of a shortcut to ensuring you don't return duplicate rows and thus get duplicate objects. You'll sometimes see people doing this as well. If you see it too much it's a real red flag. Not...
Core dump file analysis [duplicate]
...ber (replacing number with the corresponding number in the stack trace) to select a particular stack frame.
You can then use list to see code around that function, and info locals to see the local variables. You can also use print name_of_variable (replacing "name_of_variable" with a variable name)...
What is the size of column of int(11) in mysql in bytes?
...ytes (64 bit).
The length just specifies how many characters to pad when selecting data with the mysql command line client. 12345 stored as int(3) will still show as 12345, but if it was stored as int(10) it would still display as 12345, but you would have the option to pad the first five digits. ...
Error while installing json gem 'mkmf.rb can't find header files for ruby'
...installing command-line tools and accepting the license with
sudo xcode-select --install
sudo xcodebuild -license accept
The issue is that Xcode 11 ships the macOS 10.15 SDK which includes headers for ruby2.6, but not for macOS 10.14's ruby2.3. You can verify that this is your problem by runnin...
What is a “batch”, and why is GO used?
...add a column to a table, then it should be in its own batch.
If you try to SELECT the new column in the same batch it fails because at parse/compile time the column does not exist.
GO is used by the SQL tools to work this out from one script: it is not a SQL keyword and is not recognised by the eng...
What is the way to quick-switch between tabs in Xcode 4
...
Shortcuts are:
CMD + SHIFT + } - Select Next tab
CMD + SHIFT + { - Select Previous tab
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LINQ: Distinct values
...d it should be okay:
var query = doc.Elements("whatever")
.Select(element => new {
id = (int) element.Attribute("id"),
category = (int) element.Attribute("cat") })
.Distinct();
If you're trying to get a dis...
Convert a CERT/PEM certificate to a PFX certificate
... tools:
Import certificate to the certificate store. In Windows Explorer select "Install Certificate" in context menu.
Follow the wizard and accept default options "Local User" and "Automatically".
Find your certificate in certificate store. On Windows 10 run the "Manage User Certificates" MMC. ...
Using regular expression in css?
...
You can manage selecting those elements without any form of regex as the previous answers show, but to answer the question directly, yes you can use a form of regex in selectors:
#sections div[id^='s'] {
color: red;
}
That says sel...
Comparison of full text search engine - Lucene, Sphinx, Postgresql, MySQL?
... up the firstname field as shown.
http://localhost:8983/solr/collection1/select?q=firstname:john^2&lastname:john
As you can see, firstname field is boosted up with a score of 2.
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