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SQL Server SELECT into existing table
I am trying to select some fields from one table and insert them into an existing table from a stored procedure. Here is what I am trying:
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How to write a foreach in SQL Server?
... the lines of a for-each, where I would like to take the Ids of a returned select statement and use each of them.
10 Answer...
When to use Common Table Expression (CTE)
...ing well? Can someone give me a simple example of limitations with regular select, derived or temp table queries to make the case of CTE? Any simple examples would be highly appreciated.
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How to make the first option of selected with jQuery
How do I make the first option of selected with jQuery?
27 Answers
27
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WHERE vs HAVING
Why do you need to place columns you create yourself (for example select 1 as "number" ) after HAVING and not WHERE in MySQL?
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Simple way to calculate median with MySQL
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In MariaDB / MySQL:
SELECT AVG(dd.val) as median_val
FROM (
SELECT d.val, @rownum:=@rownum+1 as `row_number`, @total_rows:=@rownum
FROM data d, (SELECT @rownum:=0) r
WHERE d.val is NOT NULL
-- put some where clause here
ORDER BY d.val
) ...
Select first row in each GROUP BY group?
As the title suggests, I'd like to select the first row of each set of rows grouped with a GROUP BY .
17 Answers
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SQL Server 2008: How to query all databases sizes?
...
with fs
as
(
select database_id, type, size * 8.0 / 1024 size
from sys.master_files
)
select
name,
(select sum(size) from fs where type = 0 and fs.database_id = db.database_id) DataFileSizeMB,
(select sum(size) from fs wh...
How do SQL EXISTS statements work?
... criteria -- this is why it can be faster than IN. Also be aware that the SELECT clause in an EXISTS is ignored - IE:
SELECT s.*
FROM SUPPLIERS s
WHERE EXISTS (SELECT 1/0
FROM ORDERS o
WHERE o.supplier_id = s.supplier_id)
...should hit a division by zero error...
App Inventor 2 上传文件到服务器的方案全总结 - App Inventor 2 中文网 - ...
1、图片Base64化，然后通过Web客户端POST文本的方式，发送数据，服务端base64解码后，存储文件。下载过程是Web客户端通过网络url下载文件到手机。
类似地，也可以将图片Base64化后分片存储到网络微数据库。下...