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PostgreSQL - max number of parameters in “IN” clause?
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explain select * from test where id in (values (1), (2));
QUERY PLAN
Seq Scan on test (cost=0.00..1.38 rows=2 width=208)
Filter: (id = ANY ('{1,2}'::bigint[]))
But if try 2nd query:
explain select * from test where id = an...
How to copy a selection to the OS X clipboard
I have an area selected in Vim. How can I copy it into the OS X clipboard?
27 Answers
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LIMIT 10..20 in SQL Server
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For SQL Server 2012 + you can use.
SELECT *
FROM sys.databases
ORDER BY name
OFFSET 5 ROWS
FETCH NEXT 5 ROWS ONLY
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App Inventor 2 SQLite 拓展：超流行兼容主流SQL语法的迷你本地数据库引擎...
...原始调用中指定的标签以及新行或更新行的行 ID。
AfterSelect(tag,rowCount,rows)
此事件在异步 Select 调用后触发。
提供原始调用中指定的标签、返回的行数以及结果行数据。
AfterUpdate(tag,rowCount)
此事件在异步 Update 调用后触发。...
Ruby Arrays: select(), collect(), and map()
...re, to check the :qty key, you'd do something like the following:
details.select{ |item| item[:qty] != "" }
That will give you all items where the :qty key isn't an empty string.
official select documentation
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How to access SOAP services from iPhone
...roxy server between the iPhone and the web service? Perhaps something that converts REST into SOAP for you?
You could try CSOAP, a SOAP library that depends on libxml2 (which is included in the iPhone SDK).
I've written my own SOAP framework for OSX. However it is not actively maintained and will ...
Generating PDF files with JavaScript
I’m trying to convert XML data into PDF files from a web page and I was hoping I could do this entirely within JavaScript. I need to be able to draw text, images and simple shapes. I would love to be able to do this entirely in the browser.
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How to get a list of user accounts using the command line in MySQL?
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Use this query:
SELECT User FROM mysql.user;
Which will output a table like this:
+-------+
| User |
+-------+
| root |
+-------+
| user2 |
+-------+
As Matthew Scharley points out in the comments on this answer, you can group by the ...
Extract a dplyr tbl column as a vector
...2 3.62 3.54 4.11
A nice way to do this in v0.2 of dplyr:
iris2 %>% select(Species) %>% collect %>% .[[5]]
Or if you prefer:
iris2 %>% select(Species) %>% collect %>% .[["Species"]]
Or if your table isn't too big, simply...
iris2 %>% collect %>% .[["Species"]]
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How to paste over without overwriting register
Does anyone know of a way to paste over a visually selected area without having the selection placed in the default register?
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