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How to display Base64 images in HTML?
...age = 'http://images.itracki.com/2011/06/favicon.png';
// Read image path, convert to base64 encoding
$imageData = base64_encode(file_get_contents($image));
// Format the image SRC: data:{mime};base64,{data};
$src = 'data: '.mime_content_type($image).';base64,'.$imageData;
// Echo out a sample im...
MySQL: Insert record if not exists in table
...oDB;
Insert a record:
INSERT INTO table_listnames (name, address, tele)
SELECT * FROM (SELECT 'Rupert', 'Somewhere', '022') AS tmp
WHERE NOT EXISTS (
SELECT name FROM table_listnames WHERE name = 'Rupert'
) LIMIT 1;
Query OK, 1 row affected (0.00 sec)
Records: 1 Duplicates: 0 Warnings: 0
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How to check if an object is nullable?
...se I got a boxed Nullable<T> but because I was writing a generic WPF converter base class and some properties are nullable, so I used Nullable.GetUnderlyingType to detect that case and Activator.CreateInstance to make a boxed nullable, (Convert.ChangeType doesn't handle nullables btw).
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Trying to fix line-endings with git filter-branch, but having no luck
...s from the previous command and runs them through the utility 'fromdos' to convert the line-endings.
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Real life example, when to use OUTER / CROSS APPLY in SQL
...1) Top N per group queries (can be more efficient for some cardinalities)
SELECT pr.name,
pa.name
FROM sys.procedures pr
OUTER APPLY (SELECT TOP 2 *
FROM sys.parameters pa
WHERE pa.object_id = pr.object_id
ORDER BY pr.n...
Difference between Select Unique and Select Distinct
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SELECT UNIQUE is old syntax supported by Oracle's flavor of SQL. It is synonymous with SELECT DISTINCT.
Use SELECT DISTINCT because this is standard SQL, and SELECT UNIQUE is non-standard, and in database brands other than ...
How to subtract date/time in JavaScript? [duplicate]
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You can use getTime() method to convert the Date to the number of milliseconds since January 1, 1970. Then you can easy do any arithmetic operations with the dates. Of course you can convert the number back to the Date with setTime(). See here an example.
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initializer_list and move semantics
...zer_list.
In this example code, I used a set of small helper functions to convert the variadic arguments into a vector, to make it similar to the original code. But of course you can write a recursive function with variadic templates directly instead.
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How to get multiple counts with one SQL query?
...tion. This is basically the same thing as a PIVOT function in some RDBMS:
SELECT distributor_id,
count(*) AS total,
sum(case when level = 'exec' then 1 else 0 end) AS ExecCount,
sum(case when level = 'personal' then 1 else 0 end) AS PersonalCount
FROM yourtable
GROUP BY distributor_id
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Which selector do I need to select an option by its text?
I need to check if a <select> has an option whose text is equal to a specific value.
16 Answers
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