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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...
SQL NVARCHAR and VARCHAR Limits
... large (unavoidable) dynamic SQL query. Due to the number of fields in the selection criteria the string containing the dynamic SQL is growing over 4000 chars. Now, I understand that there is a 4000 max set for NVARCHAR(MAX) , but looking at the executed SQL in Server Profiler for the statement
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Trigger change event of dropdown
...wns, the best way to do it is to have a script that returns the a prebuilt select box and an AJAX call that requests it.
Here is the documentation for jQuery's Ajax method if you need it.
$(document).ready(function(){
$('#countrylist').change(function(e){
$this = $(e.target);
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Pandas - Get first row value of a given column
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To select the ith row, use iloc:
In [31]: df_test.iloc[0]
Out[31]:
ATime 1.2
X 2.0
Y 15.0
Z 2.0
Btime 1.2
C 12.0
D 25.0
E 12.0
Name: 0, dtype: float64
To select the ith val...
SQL Server: Examples of PIVOTing String data
...l as numbers. This query will only require the table to be scanned once.
SELECT Action,
MAX( CASE data WHEN 'View' THEN data ELSE '' END ) ViewCol,
MAX( CASE data WHEN 'Edit' THEN data ELSE '' END ) EditCol
FROM t
GROUP BY Action
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How do you copy a record in a SQL table but swap out the unique id of the new row?
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Try this:
insert into MyTable(field1, field2, id_backup)
select field1, field2, uniqueId from MyTable where uniqueId = @Id;
Any fields not specified should receive their default value (which is usually NULL when not defined).
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Remove Trailing Spaces and Update in Columns in SQL Server
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Try
SELECT LTRIM(RTRIM('Amit Tech Corp '))
LTRIM - removes any leading spaces from left side of string
RTRIM - removes any spaces from right
Ex:
update table set CompanyName = LTRIM(RTRIM(CompanyName))
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UITableView Setting some cells as “unselectable”
How can I set the UITableView's cell property to be unselectable? I don't want to see that blue selection box when the user taps on the cell.
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SQL/mysql - Select distinct/UNIQUE but return all columns?
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You're looking for a group by:
select *
from table
group by field1
Which can occasionally be written with a distinct on statement:
select distinct on field1 *
from table
On most platforms, however, neither of the above will work because the behavior o...
Getting back old copy paste behaviour in tmux, with mouse
... -g mode-mouse off
set-option -g mouse-resize-pane off
set-option -g mouse-select-pane off
set-option -g mouse-select-window off
# toggle mouse mode to allow mouse copy/paste
# set mouse on with prefix m
bind m \
set -g mode-mouse on \;\
set -g mouse-resize-pane on \;\
set -g mouse-selec...