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What's the difference between array_merge and array + array?
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The difference is:
The + operator takes the union of the two arrays, whereas the array_merge function takes the union BUT the duplicate keys are overwritten.
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How to join two sets in one line without using “|”
...are assigned sets. Without using the join operator | , how can I find the union of the two sets? This, for example, finds the intersection:
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How do I get SUM function in MySQL to return '0' if no values are found?
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Use COALESCE to avoid that outcome.
SELECT COALESCE(SUM(column),0)
FROM table
WHERE ...
To see it in action, please see this sql fiddle: http://www.sqlfiddle.com/#!2/d1542/3/0
More Information:
Given three tables (one with all numbers, one with all nul...
PreparedStatement IN clause alternatives?
... and cons of each is available here.
The suggested options are:
Prepare SELECT my_column FROM my_table WHERE search_column = ?, execute it for each value and UNION the results client-side. Requires only one prepared statement. Slow and painful.
Prepare SELECT my_column FROM my_table WHERE search_...
How to merge 2 List and removing duplicate values from it in C#
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Have you had a look at Enumerable.Union
This method excludes duplicates from the return set. This is different
behavior to the Concat
method, which returns all the elements
in the input sequences including
duplicates.
List<int> list1 = new List<int...
Can I specify a custom location to “search for views” in ASP.NET MVC?
...t viewLocations (.Union(viewLocations)) or just change them (viewLocations.Select(path => "/AnotherPath" + path)).
To register your custom view location expander in MVC, add next lines to ConfigureServices method in Startup.cs file:
public void ConfigureServices(IServiceCollection services)
{
...
error, string or binary data would be truncated when trying to insert
...ay cause it.
In my case i was creating the table with a field like this:
Select '' as Period, * From Transactions Into #NewTable
Therefore the field "Period" had a length of Zero and causing the Insert operations to fail. I changed it to "XXXXXX" that is the length of the incoming data and it n...
Difference between natural join and inner join
...+----------+
The INNER JOIN of TableA and TableB on Column1 will return
SELECT * FROM TableA AS a INNER JOIN TableB AS b USING (Column1);
SELECT * FROM TableA AS a INNER JOIN TableB AS b ON a.Column1 = b.Column1;
+------------+-----------+---------------------+
| a.Column1 | a.Column2 | ...
What is 'Pattern Matching' in functional languages?
...s similar to dynamic message dispatch) but I can't see how at run-time you select a branch without a type test.
– David Moles
Feb 17 '16 at 23:42
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Struct Constructor in C++?
...wever I think he's having a compile issue. The issue might be because of a union that is using the struct. You can't have non-trivial constructors in the type you have in a union.
– Chap
Jul 14 '09 at 20:18
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