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What is the difference between “INNER JOIN” and “OUTER JOIN”?
...he intersection of the two tables, i.e. the two rows they have in common.
select * from a INNER JOIN b on a.a = b.b;
select a.*, b.* from a,b where a.a = b.b;
a | b
--+--
3 | 3
4 | 4
Left outer join
A left outer join will give all rows in A, plus any common rows in B.
select * from a LEFT OUT...
Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
...irm this - I just updated a query with 4 joins on a 168,000 row database. Selecting just the first 100 rows with a SQL_CALC_FOUND_ROWS took over 20 seconds; using a separate COUNT(*) query took under 5 seconds (for both count + results queries).
– Sam Dufel
Ju...
xcode-select active developer directory error
...red node-gyp ... but could be triggered by anything which requires xcode-select .
23 Answers
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Difference between Select and ConvertAll in C#
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Select is a LINQ extension method and works on all IEnumerable<T> objects whereas ConvertAll is implemented only by List<T>. The ConvertAll method exists since .NET 2.0 whereas LINQ was introduced with 3.5.
You s...
How can I use pointers in Java?
...ably meant to say was:
Tiger tony = null;
tony = third; // OK.
Improper Casting:
Lion leo = new Lion();
Tiger tony = (Tiger)leo; // Always illegal and caught by compiler.
Animal whatever = new Lion(); // Legal.
Tiger tony = (Tiger)whatever; // Illegal, just as in previous example.
Lion leo = (...
Oracle SQL: Update a table with data from another table
...his is called a correlated update
UPDATE table1 t1
SET (name, desc) = (SELECT t2.name, t2.desc
FROM table2 t2
WHERE t1.id = t2.id)
WHERE EXISTS (
SELECT 1
FROM table2 t2
WHERE t1.id = t2.id )
Assuming the join results in a key-pr...
How can I convert comma separated string into a List
...
Here is one way of doing it:
List<int> TagIds = tags.Split(',').Select(int.Parse).ToList();
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postgresql return 0 if returned value is null
...eved for display.
Edit
Here's an example of COALESCE with your query:
SELECT AVG( price )
FROM(
SELECT *, cume_dist() OVER ( ORDER BY price DESC ) FROM web_price_scan
WHERE listing_Type = 'AARM'
AND u_kbalikepartnumbers_id = 1000307
AND ( EXTRACT( DAY FROM ( NOW() - ...
Mysql: Select rows from a table that are not in another
How to select all rows in one table that do not appear on another?
8 Answers
8
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Get selected text from a drop-down list (select box) using jQuery
How can I get the selected text (not the selected value) from a drop-down list in jQuery?
34 Answers
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