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Eclipse does not highlight matching variables
...y:
window > preferences > java > editor > mark occurrences
Select all options available there.
Also go to:
Preferences > General > Editors > Text Editors > Annotations
Compare the settings for 'Occurrences' and 'Write Occurrences'
Make sure that you don't have the 'T...
How to create relationships in MySQL
...s defined as the default storage engine,can check using command (mysql> SELECT @@default_storage_engine;)
– Arun
Feb 18 at 4:00
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Is there a python equivalent of Ruby's 'rvm'?
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Optionally, if you're using Macports you can use python_select.
Install python_select with:
$ sudo port install python_select
Assuming python 2.6 and 2.5 have bee installed via Macports you can switch pythons like so:
$ sudo python_select python25
=> Selecting version "pyth...
Removing fields from struct or hiding them in JSON Response
...ending back to the caller. I'd now like to allow the caller to be able to select the specific fields they would like returned by passing in a "fields" GET parameter.
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Use email address as primary key?
... key. Email address may be a bit much, but a CASCADE UPDATE for a PK of 2-character country code isn't a big deal.
– Matthew Wood
Sep 27 '10 at 20:58
5
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How to empty a redis database?
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$ redis-cli then select database. I am selecting 0 > select 0 and delete all keys of db 0 > FLUSHDB
– sagar junnarkar
May 5 '15 at 17:41
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What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
... using Standard SQL.
An obvious omission is the equivalent using EXCEPT:
SELECT a FROM table1
EXCEPT
SELECT a FROM table2
Note in Oracle you need to use the MINUS operator (arguably a better name):
SELECT a FROM table1
MINUS
SELECT a FROM table2
Speaking of proprietary syntax, there may also ...
How do I join two SQLite tables in my Android application?
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You need rawQuery method.
Example:
private final String MY_QUERY = "SELECT * FROM table_a a INNER JOIN table_b b ON a.id=b.other_id WHERE b.property_id=?";
db.rawQuery(MY_QUERY, new String[]{String.valueOf(propertyId)});
Use ? bindings instead of putting values into raw sql query.
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Difference between `const shared_ptr` and `shared_ptr`?
...);
sA->a = 4; // compile-error
return sA;
}
int main(int argc, char** argv) {
f1();
f2();
return 0;
}
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postgresql COUNT(DISTINCT …) very slow
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You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;
This is much faster than:
COUNT(DISTINCT column_name)
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