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'IF' in 'SELECT' statement - choose output value based on column values
..., IFNULL(amount,0) * -1) as amount
FROM report
The part IFNULL(amount,0) means when amount is not null return amount else return 0.
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How to efficiently build a tree from a flat structure?
...ps if x[1] == node]
}
For example:
# (child, parent) pairs where -1 means no parent
flat_tree = [
(1, -1),
(4, 1),
(10, 4),
(11, 4),
(16, 11),
(17, 11),
(24, 17),
(25, 17),
(5, 1),
(8, 5),
(9, 5),
(7, 9),
(12, 9),
(22, ...
How do I UPDATE from a SELECT in SQL Server?
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This will tend to work across almost all DBMS which means learn once, execute everywhere. If that is more important to you than performance you might prefer this answer, especially if your update is a one off to correct some data.
– Alan Macdonald
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Django REST Framework: adding additional field to ModelSerializer
...f properties in Django models, and cannot find good explanation of what it means. Can you explain? What is the point of the @property decorator here?
– Neil
Aug 23 '13 at 7:09
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INSERT statement conflicted with the FOREIGN KEY constraint - SQL Server
...'ll need to post your statement for more clarification. But...
That error means that the table you are inserting data into has a foreign key relationship with another table. Before data can be inserted, the value in the foreign key field must exist in the other table first.
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client secret in OAuth 2.0
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Also I don't understand what you mean by "If a user proxies your HTTPs call" yes users get access to data they sent using HTTPs and they are free to proxy calls however they like. As I understood you are suggesting this as quite a nice alternative to disass...
How to disable/enable select field using jQuery?
...led is a Boolean Attribute of the select element as stated by WHATWG, that means the RIGHT WAY TO DISABLE with jQuery would be
jQuery("#selectId").attr('disabled',true);
This would make this HTML
<select id="selectId" name="gender" disabled="disabled">
<option value="-1">--Select...
Add & delete view from Layout
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What will be the diff in terms of performance? I mean the performance diff of adding them dynamically or putting them into a static xml layout file and let it be inflated ?
– stdout
Jun 15 '16 at 13:24
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SQL Server 2008: How to query all databases sizes?
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I don't know exactly what you mean by efficiency but this is straightforward and it works for me:
SELECT
DB_NAME(db.database_id) DatabaseName,
(CAST(mfrows.RowSize AS FLOAT)*8)/1024 RowSizeMB,
(CAST(mflog.LogSize AS FLOAT)*8)/1024 LogSizeMB...
Facebook access token server-side validation for iPhone app
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Does this mean that you'll have to call this fb endpoint on each request? Isn't there a beter way?
– Jdruwe
Oct 8 '15 at 18:50
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