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Count, size, length…too many choices in Ruby?
...e will generate a query that requests all of the items from the database ('select * from mytable') and then give you the number of items resulting, whereas .count will generate a single query ('select count(*) from mytable') which is considerably faster.
Because these ORMs are so prevalent I follow...
What is the difference between a pseudo-class and a pseudo-element in CSS?
...
The CSS 3 selector recommendation is pretty clear about both, but I'll try to show the differences anyway.
Pseudo-classes
Official description
The pseudo-class concept is introduced to permit selection based on information that l...
Markdown to create pages and table of contents?
...nd to generate the TOC, open the command palette (Control/⌘+Shift+P) and select the Select Markdown: Create Table of Contentsoption.
Another option is the Markdown TOC plugin.
To install it, launch the VS Code Quick Open (Control/⌘+P), paste the following command, and press enter.
ext install m...
Running JAR file on Windows
...e Environment (JRE).
Or this:
Open the Windows Explorer, from the Tools select 'Folder Options...'
Click the File Types tab, scroll down and select JAR File type.
Press the Advanced button.
In the Edit File Type dialog box, select open in Actions box and click Edit...
Press the Browse button and ...
MySQL 'create schema' and 'create database' - Is there any difference
...asn't been allocated to any particular schema, you can do something like:
SELECT *
FROM your_table
which is equivalent to:
SELECT *
FROM dbo.your_table
Now, SQL server allows the creation of different schema, which gives you the possibility of grouping tables that share a similar purpose. That...
What can you use Python generator functions for?
...uld like to update Alexa rank for each domain.
First thing you need is to select your domain names from the database.
Let's say your table name is domains and column name is domain.
If you use SELECT domain FROM domains it's going to return 100 million rows which is going to consume lot of memory...
How do I get a raw, compiled SQL query from a SQLAlchemy expression?
...
@cce: you're trying to find the final query. SELECT id WHERE date_added <= %s AND date_added >= %s ORDER BY count DESC IS the final query. Those %s are sent to the database by sqlalchemy -- sqlalchemy NEVER puts the actual data in place of the %s
...
Proper Linq where clauses
...cate are combined and only one iterator is involed. Look atEnumerable.WhereSelectEnumerableIterator.
– Cybermaxs
Apr 4 '13 at 12:46
...
How to create a database from shell command?
... I get this error ERROR 1046 (3D000) at line 27: No database selected when I run echo "create database databasename" | mysql -u -u username -p command
– keerthi
Mar 15 '13 at 5:16
...
How to use a WSDL
... the project and pick Connected Service from the Add context menu.
I would select Microsoft WCF Web Service Reference Provider from the list.
I would press browse and select the wsdl file straight away, Set the namespace and I am good to go.
Refer to the error fix url above if you encounter any err...