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How do I calculate tables size in Oracle
...BLE_NAME FORMAT A32
COLUMN OBJECT_NAME FORMAT A32
COLUMN OWNER FORMAT A10
SELECT
owner,
table_name,
TRUNC(sum(bytes)/1024/1024) Meg,
ROUND( ratio_to_report( sum(bytes) ) over () * 100) Percent
FROM
(SELECT segment_name table_name, owner, bytes
FROM dba_segments
WHERE segment_type IN...
how do I query sql for a latest record date for each user
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select t.username, t.date, t.value
from MyTable t
inner join (
select username, max(date) as MaxDate
from MyTable
group by username
) tm on t.username = tm.username and t.date = tm.MaxDate
...
Default text which won't be shown in drop-down list
I have a select which initially shows Select language until the user selects a language. When the user opens the select, I don't want it to show a Select language option, because it's not an actual option.
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Passing an array to a query using a WHERE clause
...y external input is sanitized.
$ids = join("','",$galleries);
$sql = "SELECT * FROM galleries WHERE id IN ('$ids')";
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What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...'t, then use DISTINCT.
GROUP BY in MySQL sorts results. You can even do:
SELECT u.profession FROM users u GROUP BY u.profession DESC
and get your professions sorted in DESC order.
DISTINCT creates a temporary table and uses it for storing duplicates. GROUP BY does the same, but sortes the disti...
Can an Android Toast be longer than Toast.LENGTH_LONG?
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The values of LENGTH_SHORT and LENGTH_LONG are 0 and 1. This means they are treated as flags rather than actual durations so I don't think it will be possible to set the duration to anything other than these values.
If you want to display a message t...
How do I perform an IF…THEN in an SQL SELECT?
How do I perform an IF...THEN in an SQL SELECT statement?
30 Answers
30
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Vim search and replace selected text
Let's say we have a text, and I enter visual mode and select some text. How do I quickly do a search for the highlighted text and replace it with something else?
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MPICH vs OpenMPI
...make it the preferred implementation in nearly all cases.
Feature Support from the Latest MPI Standard
An orthogonal axis to hardware/platform support is coverage of the MPI standard. Here MPICH is usually far and away superior. MPICH has been the first implementation of every single release of ...
Reference alias (calculated in SELECT) in WHERE clause
The calculated value BalanceDue that is set as a variable in the list of selected columns cannot be used in the WHERE clause.
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