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SQL Server : Columns to Rows
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You can use the UNPIVOT function to convert the columns into rows:
select id, entityId,
indicatorname,
indicatorvalue
from yourtable
unpivot
(
indicatorvalue
for indicatorname in (Indicator1, Indicator2, Indicator3)
) unpiv;
Note, the datatypes of the columns you are unpivoting mus...
MySQL selecting yesterday's date
...get yesterday's date is:
subdate(current_date, 1)
Your query would be:
SELECT
url as LINK,
count(*) as timesExisted,
sum(DateVisited between UNIX_TIMESTAMP(subdate(current_date, 1)) and
UNIX_TIMESTAMP(current_date)) as timesVisitedYesterday
FROM mytable
GROUP BY 1
For the ...
When should I use cross apply over inner join?
...APPLY works better on things that have no simple JOIN condition.
This one selects 3 last records from t2 for each record from t1:
SELECT t1.*, t2o.*
FROM t1
CROSS APPLY
(
SELECT TOP 3 *
FROM t2
WHERE t2.t1_id = t1.id
ORDER BY
t2.ran...
SQL JOIN and different types of JOINs
...
There are relatively new LATERAL JOIN .. SELECT * FROM r1, LATERAL fx(r1)
– Pavel Stehule
Jul 30 '13 at 11:52
13
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SQL Server dynamic PIVOT query?
... @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX);
SET @cols = STUFF((SELECT distinct ',' + QUOTENAME(c.category)
FROM temp c
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'')
set @query = 'SELECT date, ' + @cols + ' from
(...
Targeting S+ (version 31 and above) requires that one of FLAG_IMMUTABL...
运行故障：edu.mit.appinventor aicompanion3: Targeting S+ (version 31 and above) requires that one of FLAG_IMMUTABLE or FLAG_MUTABLE be specified when creating a PendingIntent. Strongly consider using FLAG IMMUTABLE, only use FLAG_MUTABLE if some functionality depends on the PendingIntent being ...
Call to ‘set-and-coerce-property!’ has too few arguments (3; must be...
编译apk，报错：Call to ‘set-and-coerce-property!’ has too few arguments (3; must be 4)
原因是因为代码块有问题/报错，有空的地方没有填值，比如这种：
参考：https://community.appinventor.mi ... 3-must-be-4/20690/4
又学习到了新bug的解决方法...
Service and Characteristic are not published by the connected device -...
Service and Characteristic are not published by the connected device，报错如下：
问题原因：硬件/蓝牙芯片问题导致的，比如A硬件测试好的，换了B硬件没有修改uuid，就出现这个报错。
由于B硬件没有发布这些特征，就会报这个错误。
How to get cumulative sum
the above select returns me the following.
16 Answers
16
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How to select only 1 row from oracle sql?
I want to use oracle syntax to select only 1 row from table DUAL . For example, I want to execute this query:
13 Answers
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