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Insertion Sort vs. Selection Sort
I am trying to understand the differences between Insertion Sort and Selection Sort.
20 Answers
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How to use count and group by at the same select statement
I have an sql select query that has a group by.
I want to count all the records after the group by statement.
Is there a way for this directly from sql?
For example, having a table with users I want to select the different towns and the total number of users
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Saving enum from select in Rails 4.1
...num.
I changed the input to be the following:
f.input :color, :as => :select, :collection => Wine.colors.keys.to_a
Which generated the following HTML:
<select id="wine_color" name="wine[color]">
<option value=""></option>
<option value="red">red</option>
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How to select unique records by SQL
When I perform "SELECT * FROM table" I got results like below:
8 Answers
8
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Convert Rows to columns using 'Pivot' in SQL Server
...9, 3, 87);
If your values are known, then you will hard-code the query:
select *
from
(
select store, week, xCount
from yt
) src
pivot
(
sum(xcount)
for week in ([1], [2], [3])
) piv;
See SQL Demo
Then if you need to generate the week number dynamically, your code will be:
DECLARE @c...
Forward declaring an enum in C++
...ifferent sizes, but I'm fairly sure that data pointers have to round-trip (cast to another data pointer type, then back to the original, need to still work), which implies that all data pointers are the same size.
– Ben Voigt
Mar 9 '10 at 4:53
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How to select option in drop down protractorjs e2e tests
I am trying to select an option from a drop down for the angular e2e tests using protractor.
31 Answers
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Efficient SQL test query or validation query that will work across all (or most) databases
...er a little bit of research along with help from some of the answers here:
SELECT 1
H2
MySQL
Microsoft SQL Server (according to NimChimpsky)
PostgreSQL
SQLite
SELECT 1 FROM DUAL
Oracle
SELECT 1 FROM any_existing_table WHERE 1=0
or
SELECT 1 FROM INFORMATION_SCHEMA.SYSTEM_USERS
or
CALL NOW()
HS...
SQL Server: SELECT only the rows with MAX(DATE)
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If rownumber() over(...) is available for you ....
select OrderNO,
PartCode,
Quantity
from (select OrderNO,
PartCode,
Quantity,
row_number() over(partition by OrderNO order by DateEntered desc) as rn
from YourTable) a...
SELECT INTO Variable in MySQL DECLARE causes syntax error?
I´d like to SELECT a single value into a variable. I´d tried to following:
11 Answers
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