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Algorithm to find top 10 search terms
...ue ID for each. This whole set of data can be loaded into memory as a hash table, consuming roughly 300MB memory. (We have implemented our own hash table. The Java's implementation takes huge memory overhead)
Each phrase then can be identified as an array of integers.
This is important, because s...
Function to Calculate Median in SQL Server
... the 7 years since, but personally I wouldn't use this function on a large table until I verified its performance vs. other solutions.
ORIGINAL 2009 POST IS BELOW:
There are lots of ways to do this, with dramatically varying performance. Here's one particularly well-optimized solution, from Median...
When NOT to use Cassandra?
...zing log data, or any place where scanning huge, two-dimensional join-less tables is a requirement. Redis is built to provide In-Memory search for varieties of data structures like trees, queues, linked lists, etc and can be a good fit for making real-time leaderboards, pub-sub kind of system. Simil...
LIMIT 10..20 in SQL Server
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You example query runs fine but If I change the table name and order by col as below SELECT * FROM DimProduct ORDER BY ProductKey OFFSET 5 ROWS FETCH NEXT 5 ROWS ONLY It gives error Parse error at line: 4, column: 1: Incorrect syntax near 'OFFSET'
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Check if a Postgres JSON array contains a string
I have a table to store information about my rabbits. It looks like this:
4 Answers
4
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Amazon SimpleDB vs Amazon DynamoDB
...best parts of
the original Dynamo design (incremental scalability, predictable high
performance) with the best parts of SimpleDB (ease of administration
of a cloud service, consistency, and a table-based data model that is
richer than a pure key-value store).
Werner's Summary suggests Dyna...
Have bash script answer interactive prompts [duplicate]
...[yes]`
`#Skip plural name checking [no]`
`#Use logged storage [no]`
`#Sort tables and views [yes]`
`#Export only table categorized []`
`#Enhance many to many detection [yes]`
`#Skip many to many tables [yes]`
`#Bundle namespace []`
`#Entity namespace []`
`#Repository namespace []`
`#Use automatic re...
Sample random rows in dataframe
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The data.table package provides the function DT[sample(.N, M)], sampling M random rows from the data table DT.
library(data.table)
set.seed(10)
mtcars <- data.table(mtcars)
mtcars[sample(.N, 6)]
mpg cyl disp hp drat wt ...
Get generated id after insert
... @GrAnd, but what if I'll delete some "start-middle" rows in my table, so I break the sequence of n-th rows with generated id=n. Will that returned row ID remain the same as generated autoincrement id?
– UnknownJoe
Jan 28 '14 at 9:07
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Inserting a Python datetime.datetime object into MySQL
I have a date column in a MySQL table. I want to insert a datetime.datetime() object into this column. What should I be using in the execute statement?
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