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How to insert a line break in a SQL Server VARCHAR/NVARCHAR string
...NVARCHAR(100)
SET @text = 'This is line 1.' + CHAR(13) + 'This is line 2.'
SELECT @text
This prints out the following:
This is line 1.
This is line 2.
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SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
...result set to update is before running the update (same query, just with a select):
select *
from QuestionTrackings q
inner join QuestionAnswers a
on q.AnswerID = a.AnswerID
where q.QuestionID is null -- and other conditions you might want
Particularly whether each answer id has definitely only 1...
How do I get the size of a java.sql.ResultSet?
...
Do a SELECT COUNT(*) FROM ... query instead.
OR
int size =0;
if (rs != null)
{
rs.last(); // moves cursor to the last row
size = rs.getRow(); // get row id
}
In either of the case, you won't have to loop over the enti...
How to print SQL statement in codeigniter model
...veRecord generated SQL:
Before the query runs:
$this->db->_compile_select();
And after it has run:
$this->db->last_query();
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Escape Character in SQL Server
...s the second answer shows it's possible to escape single quote like this:
select 'it''s escaped'
result will be
it's escaped
If you're concatenating SQL into a VARCHAR to execute (i.e. dynamic SQL), then I'd recommend parameterising the SQL. This has the benefit of helping guard against SQL in...
Extracting specific columns from a data frame
...r package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
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How to get equal width of input and select fields
On the form, I have one select and two input fields. These elements are vertically aligned. Unfortunately, I can't get equal width of these elements.
...
How to deselect a selected UITableView cell?
I am working on a project on which I have to preselect a particular cell.
24 Answers
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Selecting only first-level elements in jquery
How can I select the link elements of only the parent <ul> from a list like this?
10 Answers
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Calculate difference between two datetimes in MySQL
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USE TIMESTAMPDIFF MySQL function. For example, you can use:
SELECT TIMESTAMPDIFF(SECOND, '2012-06-06 13:13:55', '2012-06-06 15:20:18')
In your case, the third parameter of TIMSTAMPDIFF function would be the current login time (NOW()). Second parameter would be the last login time, w...