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How important is the order of columns in indexes?
I've heard that you should put columns that will be the most selective at the beginning of the index declaration. Example:
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Remove Trailing Spaces and Update in Columns in SQL Server
...
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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Extract date (yyyy/mm/dd) from a timestamp in PostgreSQL
... to a date by suffixing it with ::date. Here, in psql, is a timestamp:
# select '2010-01-01 12:00:00'::timestamp;
timestamp
---------------------
2010-01-01 12:00:00
Now we'll cast it to a date:
wconrad=# select '2010-01-01 12:00:00'::timestamp::date;
date
------------
201...
How can I confirm a database is Oracle & what version it is using SQL?
I'm building an installer for an application. The user gets to select a datasource they have configured and nominate what type of database it is. I want to confirm that the database type is indeed Oracle, and if possible, what version of Oracle they are running by sending a SQL statement to the dat...
Clear form field after select for jQuery UI Autocomplete
I'm developing a form, and using jQuery UI Autocomplete. When the user selects an option, I want the selection to pop into a span appended to the parent <p> tag. Then I want the field to clear rather than be populated with the selection.
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T-SQL get SELECTed value of stored procedure
...UTPUT parameter and a result set
ALSO, watch out if you use the pattern: SELECT @Variable=column FROM table ...
if there are multiple rows returned from the query, your @Variable will only contain the value from the last row returned by the query.
RETURN VALUE
since your query returns an int fie...
Difference between two dates in MySQL
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SELECT TIMEDIFF('2007-12-31 10:02:00','2007-12-30 12:01:01');
-- result: 22:00:59, the difference in HH:MM:SS format
SELECT TIMESTAMPDIFF(SECOND,'2007-12-30 12:01:01','2007-12-31 10:02:00');
-- result: 79259 the differenc...
Select SQL Server database size
...
Try this one -
Query:
SELECT
database_name = DB_NAME(database_id)
, log_size_mb = CAST(SUM(CASE WHEN type_desc = 'LOG' THEN size END) * 8. / 1024 AS DECIMAL(8,2))
, row_size_mb = CAST(SUM(CASE WHEN type_desc = 'ROWS' THEN size END) ...
Linq to Entities - SQL “IN” clause
... be used interchangeably depending on your preference:
Query Syntax:
var selected = from u in users
where new[] { "Admin", "User", "Limited" }.Contains(u.User_Rights)
select u
foreach(user u in selected)
{
//Do your stuff on each selected user;
}
Method Syntax:...
Rename package in Android Studio
...n:
In your Project pane, click on the little gear icon ( )
Uncheck / De-select the Compact Empty Middle Packages option
Your package directory will now be broken up in individual directories
Individually select each directory you want to rename, and:
Right-click it
Select Refactor
Click o...