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Two single-column indexes vs one two-column index in MySQL?
... the statement I provided.
Additionally, MySQL can only use one index per SELECT so a covering index would be the best means of optimizing your queries.
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How do I grant myself admin access to a local SQL Server instance?
...he "SQL Server Configuration Manager", right click the server instance and select properties, go to the tab "Startup Parameters" and add -m.
– maets
May 5 '15 at 13:32
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What is the difference between Views and Materialized Views in Oracle?
... you. The downside of a view is that its performance depends on how good a select statement the view is based on. If the select statement used by the view joins many tables, or uses joins based on non-indexed columns, the view could perform poorly.
Materialized views
They are similar to regular vi...
Build Android Studio app via command line
I want to build an Android Studio app (the Gradle build system), but I want to do this via the command line.
12 Answers
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Is having an 'OR' in an INNER JOIN condition a bad idea?
... a MERGE JOIN.
It can be expressed as a concatenation of two resultsets:
SELECT *
FROM maintable m
JOIN othertable o
ON o.parentId = m.id
UNION
SELECT *
FROM maintable m
JOIN othertable o
ON o.id = m.parentId
, each of them being an equijoin, however, SQL Server's optimiz...
How to send email via Django?
...s perfect. Note the small typo correction in the comments of the article. (And I just used my regular computer/localhost. I had not set anything else up before hand.)
– user984003
Oct 24 '12 at 16:11
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Explain ExtJS 4 event handling
...js4.1)
Lets say we have a controller Station (Sencha MVC examples) with a select box:
Ext.define('Pandora.controller.Station', {
extend: 'Ext.app.Controller',
...
init: function() {
this.control({
'stationslist': {
selectionchange: this.onStationSel...
How do I temporarily disable triggers in PostgreSQL?
...ct = 'disable';
else
act = 'enable';
end if;
for r in select c.relname from pg_namespace n
join pg_class c on c.relnamespace = n.oid and c.relhastriggers = true
where n.nspname = nsp
loop
execute format('alter table %I %s trigger all', r.relname, act)...
Unexpected results when working with very big integers on interpreted languages
...he sum of 1 + 2 + ... + 1000000000 , but I'm getting funny results in PHP and Node.js .
36 Answers
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How do you search an amazon s3 bucket?
...to access many nodes at once ala more traditional datastores that offer a (SELECT * FROM ... WHERE ...) (in a SQL model).
What you will need to do is perform ListBucket to get a listing of objects in the bucket and then iterate over every item performing a custom operation that you implement - whic...