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Real life example, when to use OUTER / CROSS APPLY in SQL
I have been looking at CROSS / OUTER APPLY with a colleague and we're struggling to find real life examples of where to use them.
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NUnit Unit tests not showing in Test Explorer with Test Adapter installed
...-> "Default Processor Architecture" -> "x64"
– Andrew Rondeau
Jul 19 '18 at 19:11
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show 1 more comment
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C# SQL Server - Passing a list to a stored procedure
... con = new SqlConnection(connstring))
{
con.Open();
using (SqlCommand cmd = new SqlCommand("exec sp_UseStringList @list", con))
{
using (var table = new DataTable()) {
table.Columns.Add("Item", typeof(string));
for (int i = 0; i < 10; i++)
tab...
How to import multiple .csv files at once?
...you have those CSVs in a single directory--your current working directory--and that all of them have the lower-case extension .csv.
If you then want to combine those data frames into a single data frame, see the solutions in other answers using things like do.call(rbind,...), dplyr::bind_rows() or ...
Does the join order matter in SQL?
Disregarding performance, will I get the same result from query A and B below? How about C and D?
4 Answers
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PostgreSQL: Which Datatype should be used for Currency?
...re currencies, such as Bahrain Dinar, where 1000 sub-units equal one unit, and there are currencies which don't have sub-units at all.
– Nikolay Arhipov
Aug 24 '18 at 5:49
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Why can't C# interfaces contain fields?
For example, suppose I want an ICar interface and that all implementations will contain the field Year . Does this mean that every implementation has to separately declare Year ? Wouldn't it be nicer to simply define this in the interface?
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Mongodb Explain for Aggregation framework
...t, $geonear at the beginning of a pipeline) as well as subsequent $lookup and $graphLookup stages. Once data has been fetched into the aggregation pipeline for processing (e.g. passing through stages like $project, $unwind, and $group) further manipulation will be in-memory (possibly using temporar...
How do you find the row count for all your tables in Postgres
...g number to monitor.
The third way is to note that the system ANALYZE command, which is executed by the autovacuum process regularly as of PostgreSQL 8.3 to update table statistics, also computes a row estimate. You can grab that one like this:
SELECT
nspname AS schemaname,relname,reltuples
FR...
C++ static virtual members?
Is it possible in C++ to have a member function that is both static and virtual ? Apparently, there isn't a straightforward way to do it ( static virtual member(); is a compile error), but is there at least a way to achieve the same effect?
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