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SQL: How to get the count of each distinct value in a column?
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SELECT
category,
COUNT(*) AS `num`
FROM
posts
GROUP BY
category
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Subqueries vs joins
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Here's an example of how subqueries are evaluated in MySQL 6.0.
The new optimizer will convert this kind of subqueries into joins.
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How to copy from CSV file to PostgreSQL table with headers in CSV file?
...'','' quote ''"'' csv ', csv_file_path);
iter := 1;
col_first := (select col_1
from temp_table
limit 1);
-- update the column names based on the first row which has the column names
for col in execute format ('select unnest(string_to_array(trim(t...
Specify multiple attribute selectors in CSS
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For concatenating it's:
input[name="Sex"][value="M"] {}
And for taking union it's:
input[name="Sex"], input[value="M"] {}
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Where can I find the TypeScript version installed in Visual Studio?
...2013 ->
Visual Studio Tools A windows is open with a list of tool.
Select Developer Command Prompt for VS2013
In the opened Console write: tsc -v
You get the version: See Image
[UPDATE]
If you update your Visual Studio to a new version of Typescript as 1.0.x you don't see the last ver...
Xcode 5.1 - No architectures to compile for (ONLY_ACTIVE_ARCH=YES, active arch=x86_64, VALID_ARCHS=i
... @EmilMarashliev just the build target. You'll see it when you select your root project (with blue icon).
– Kjuly
Mar 14 '14 at 17:57
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Can table columns with a Foreign Key be NULL?
... otherwise an empty string can be passed as default. This is the case with MySQL, and results in an integrity error on update.
– CodeMantle
Mar 21 at 8:28
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CSS selector for a checked radio button's label
...ol:
It is Adjacent sibling combinator. It combines two sequences of simple selectors having the same parent and the second one must come IMMEDIATELY after the first.
As such:
input[type="radio"]:checked+label{ font-weight: bold; }
//a label that immediately follows an input of type radio that is...
Database Structure for Tree Data Structure
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Have a look at Managing Hierarchical Data in MySQL. It discusses two approaches for storing and managing hierarchical (tree-like) data in a relational database.
The first approach is the adjacency list model, which is what you essentially describe: having a foreign key...
How to set background color of an Activity to white programmatically?
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Get a handle to the root layout used, then set the background color on that. The root layout is whatever you called setContentView with.
setContentView(R.layout.main);
// Now get a handle to any View contained
// within the main layout y...