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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...
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
...
SQL MAX of multiple columns?
...
Well, you can use the CASE statement:
SELECT
CASE
WHEN Date1 >= Date2 AND Date1 >= Date3 THEN Date1
WHEN Date2 >= Date1 AND Date2 >= Date3 THEN Date2
WHEN Date3 >= Date1 AND Date3 >= Date2 THEN Date3
ELSE ...
What exactly do “u” and “r” string flags do, and what are raw string literals?
...by calling unicode('text')
So u is just a short way to call a function to cast str to unicode. That's it!
Now the r part, you put it in front of the text to tell the computer that the text is raw text, backslash should not be an escaping character. r'\n' will not create a new line character. It's ...
SQL Server : Columns to Rows
...
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...
Can you create nested WITH clauses for Common Table Expressions?
..., the form of the statement you are looking for would be
WITH x AS
(
SELECT * FROM MyTable
),
y AS
(
SELECT * FROM x
)
SELECT * FROM y
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Disabling user selection in UIWebView
...use I want the user to be able to click links. I just need to disable user selection. I found somewhere in the Internets that you can use:
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How to compare two colors for similarity/difference
...t;/b> pctDiffRed = diffRed / 255; is going to give you 0 unless you cast to a float somewhere. <b>2</b> You'll need to multiply by 100 somewhere to get a percentage.
– vaughandroid
Jan 26 '12 at 12:34
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Selecting a row in DataGridView programmatically
How can I select a particular range of rows in a DataGridView programmatically at runtime?
8 Answers
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How to use Checkbox inside Select Option
The client has given me a design which has a Select Option menu containing a checkbox together with the item name as individual items in the list.
Is there anyway possible to add a checkbox inside a Select Option menu?
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