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SQL Server loop - how do I loop through a set of records
how do I loop through a set of records from a select?
8 Answers
8
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How to get last N records with activerecord?
...e-wise - at least not up to Rails 3.1. SomeModel.last(5) will execute the select statement without a limit, returning all records of SomeModel to Ruby as an array, after which Ruby will pick out the last (5) elements. Efficiency-wise, currently, you want to use limit - particularly if you have pote...
Add a column to a table, if it does not already exist
...onstruct by using the sys.columns table io sys.objects.
IF NOT EXISTS (
SELECT *
FROM sys.columns
WHERE object_id = OBJECT_ID(N'[dbo].[Person]')
AND name = 'ColumnName'
)
share
|
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How to split a string in shell and get the last field
...ecially handy when parsing paths that could contain (or not) a finishing / character.
– eckes
Jan 23 '13 at 15:23
...
Create tap-able “links” in the NSAttributedString of a UILabel?
...tureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleTapOnLabel:)]];
Now the most sophisticated stuff: finding out whether the tap was on where the link is displayed and not on any other portion of the label. If we had single-lined UILabel, this task could be ...
Best way to do multi-row insert in Oracle?
...acle:
insert into pager (PAG_ID,PAG_PARENT,PAG_NAME,PAG_ACTIVE)
select 8000,0,'Multi 8000',1 from dual
union all select 8001,0,'Multi 8001',1 from dual
The thing to remember here is to use the from dual statement.
(source)
...
Regular cast vs. static_cast vs. dynamic_cast [duplicate]
...For example, the C-style cast would allow an integer pointer to point to a char.
char c = 10; // 1 byte
int *p = (int*)&c; // 4 bytes
Since this results in a 4-byte pointer pointing to 1 byte of allocated memory, writing to this pointer will either cause a run-time error or will overwri...
Get top 1 row of each group
...
;WITH cte AS
(
SELECT *,
ROW_NUMBER() OVER (PARTITION BY DocumentID ORDER BY DateCreated DESC) AS rn
FROM DocumentStatusLogs
)
SELECT *
FROM cte
WHERE rn = 1
If you expect 2 entries per day, then this will arbitrarily pick one...
How can I do an UPDATE statement with JOIN in SQL Server?
...oesn't support MERGE):
ANSI/ISO:
update ud
set assid = (
select sale.assid
from sale
where sale.udid = ud.id
)
where exists (
select *
from sale
where sale.udid = ud.id
);
MySQL:
update ud u
inner join sale s on
u.id = s.udid
...
How can I shift-select multiple checkboxes like GMail?
... can click on one checkbox in the email list, hold down the Shift key, and select a second checkbox. The JavaScript will then select/unselect the checkboxes that are between the two checboxes.
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