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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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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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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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String difference in Bash
.... I could easily do this with diff or comm, but I'm not dealing with files and I'd prefer not to output them to files, do the compare and read it back.
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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 ...
Convert float to double without losing precision
I have a primitive float and I need as a primitive double. Simply casting the float to double gives me weird extra precision. For example:
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Jenkins Git Plugin: How to build specific tag?
... git plugin to just build that tag. This has been taking 3 hours of my day and I have conceded defeat to the masters at stack overflow.
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Getting root permissions on a file inside of vi? [closed]
Often while editing config files, I'll open one with vi and then when I go to save it realize that I didn't type
10 Answers...
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...