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How do I format a number with commas in T-SQL?
...p_spaceused in SQL Server 2008 to look at data/index space ratios of some tables in my database. Of course I am getting all sorts of large numbers in the results and my eyes are starting to gloss over. It would be really convenient if I could format all those numbers with commas (987654321 become...
Determine whether an array contains a value [duplicate]
...oject and nowadays it's Babel :) big win for JavaScript community! There's table of what's available of ES7 already on many platforms including babel pollyfils kangax.github.io/compat-table/es2016plus
– Lukas Liesis
Jul 12 '16 at 9:52
...
Paste multiple columns together
...# 3 3 c-f-i
Alternatively we could update data in place using the data.table package (assuming fresh data)
library(data.table)
setDT(data)[, x := Reduce(function(...) paste(..., sep = "-"), .SD[, mget(cols)])]
data[, (cols) := NULL]
data
# a x
# 1: 1 a-d-g
# 2: 2 b-e-h
# 3: 3 c-f-i
Ano...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
If I have a table
15 Answers
15
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WCF vs ASP.NET Web API [closed]
...
this table is meaningless. "JQuery" (scare quotes for the capital J) is a protocol and/or format?
– hyankov
Sep 2 '17 at 18:39
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DbEntityValidationException - How can I easily tell what caused the error?
...k whether the property's value is out of range, like when you designed the table. Table_Column_UserName is varchar(20). But, in EF, you entered a value that longer than 20.
Or, in other cases, if the column does not allow to be a Null.
So, in the validation process, you have to set a value to the n...
Comparing date ranges
... |-----| equal start with end of comparison period
If your table has columns called range_end and range_start, here's some simple SQL to retrieve all the matching rows:
SELECT *
FROM periods
WHERE NOT (range_start > @check_period_end
OR range_end < @check_period_s...
How do HTML parses work if they're not using regexp?
... weirdness, trying to make the result look as good as you can and the inevitable failure the least painful... this is not something you can do with regexes.
– SF.
Mar 8 '10 at 11:16
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Query for documents where array size is greater than 1
... @Tobia my first use was $exists only but it actually use whole table scan so very slow. db.test.find({"name":"abc","d.5":{$exists:true},"d.6":{$exists:true}}) "nReturned" : 46525, "executionTimeMillis" : 167289, "totalKeysExamined" : 10990840, "totalDocsExamined" : 10990840, ...
What algorithm gives suggestions in a spell checker?
...nction.
Insert all of your dictionary words into an auxiliary index (hash table) using this special hash function. The buckets in this table will have longish collision lists because the hash function is "bad", but those collision lists are essentially pre-computed suggestions.
Now, when you find...