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What is a columnar database?
...isn't one particular description on how these databases work; indeed, several are build upon traditional, row-oriented, DBMS, simply storing the info in tables with one (or rather often two) columns (and adding the necessary layer to access the columnar data in an easy fashion).
How do they differ ...
What is the difference between `let` and `var` in swift?
...ead.
The var defines an ordinary variable.
What is interesting:
The value of a constant doesn’t need to be known at compile time, but you must assign the value exactly once.
Another strange feature:
You can use almost any character you like for constant and variable
names, including ...
Configuration With Same Name Already Exists
...re using the drop down list from the grid (not the one at the top of the dialog), and do not check the "Create new solution configurations" checkbox when adding your new project configuration.
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What is difference between CrudRepository and JpaRepository interfaces in Spring Data JPA?
...ch.
Because of the inheritance mentioned above, JpaRepository will have all the functions of CrudRepository and PagingAndSortingRepository. So if you don't need the repository to have the functions provided by JpaRepository and PagingAndSortingRepository , use CrudRepository.
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How can I consume a WSDL (SOAP) web service in Python?
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There is a relatively new library which is very promising and albeit still poorly documented, seems very clean and pythonic: python zeep.
See also this answer for an example.
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XAMPP - Port 80 in use by “Unable to open process” with PID 4! 12
...rator and execute the following command:
net stop was /y
Open the Run dialog box (press Win+R), then type: services.msc
Then search for World Wide Web Publishing Service (WWW-Publishing Service) and Web Deployment Agent Service and stop them. You should also disable them.
Start Apache again with...
How to get multiple counts with one SQL query?
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You can use a CASE statement with an aggregate function. 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) A...
How to add leading zeros?
...rt version: use formatC or sprintf.
The longer version:
There are several functions available for formatting numbers, including adding leading zeroes. Which one is best depends upon what other formatting you want to do.
The example from the question is quite easy since all the values have the ...
What is an index in SQL?
...refman/5.0/en/mysql-indexes.html
An index can be used to efficiently find all rows matching some column in your query and then walk through only that subset of the table to find exact matches. If you don't have indexes on any column in the WHERE clause, the SQL server has to walk through the whole ...
Defining a variable with or without export
...ort makes the variable available to sub-processes.
That is,
export name=value
means that the variable name is available to any process you run from that shell process. If you want a process to make use of this variable, use export, and run the process from that shell.
name=value
means the var...