大约有 46,000 项符合查询结果（耗时：0.0493秒） [XML]
IN clause and placeholders
...mes = { "name1", "name2" }; // do whatever is needed first
String query = "SELECT * FROM table"
+ " WHERE name IN (" + makePlaceholders(names.length) + ")";
Cursor cursor = mDb.rawQuery(query, names);
Just make sure to pass exactly as many values as places. The default maximum limit of host pa...
Node.js on multi-core machines
... must miss something - isn't Node.js tuned only to run on a single process and thread?
15 Answers
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Oracle “Partition By” Keyword
...d then use that in a calculation against this records salary without a sub select, which is much faster.
Read the linked AskTom article for further details.
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Only read selected columns
...from the data.table-package:
You can specify the desired columns with the select parameter from fread from the data.table package. You can specify the columns with a vector of column names or column numbers.
For the example dataset:
library(data.table)
dat <- fread("data.txt", select = c("Year...
How do I set the selected item in a comboBox to match my string using C#?
..." and my comboBox contains test1 , test2 , and test3 . How do I set the selected item to "test1"? That is, how do I match my string to one of the comboBox items?
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Oracle “(+)” Operator
...dize OUTER joins.
The query would be re-written in ANSI-92 syntax as:
SELECT ...
FROM a
LEFT JOIN b ON b.id = a.id
This link is pretty good at explaining the difference between JOINs.
It should also be noted that even though the (+) works, Oracle recommends not using it:
Oracle re...
Rails ActiveRecord date between
...ne day. The field is part of the standard timestamps, is created_at . The selected date is coming from a date_select .
11...
Execute ssh with password authentication via windows command prompt
I need to execute ssh from windows command line by providing password in a non interactive manner. I could implement the key based authentication and able to execute the ssh commands just like
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Select 50 items from list at random to write to file
... leaving the original population unchanged. The resulting list is
in selection order so that all sub-slices will also be valid random
samples. This allows raffle winners (the sample) to be partitioned
into grand prize and second place winners (the subslices).
Members of the popul...
Is it possible to use JS to open an HTML select to show its option list? [duplicate]
Is it possible to use JavaScript to open an HTML select to show its option list?
11 Answers
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