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Which is faster/best? SELECT * or SELECT column1, colum2, column3, etc
I've heard that SELECT * is generally bad practice to use when writing SQL commands because it is more efficient to SELECT columns you specifically need.
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How do you find the disk size of a Postgres / PostgreSQL table and its indexes
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Try the Database Object Size Functions. An example:
SELECT pg_size_pretty(pg_total_relation_size('"<schema>"."<table>"'));
For all tables, something along the lines of:
SELECT
table_schema || '.' || table_name AS table_full_name,
pg_size_pretty(pg_total_...
MySQL JOIN the most recent row only?
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You may want to try the following:
SELECT CONCAT(title, ' ', forename, ' ', surname) AS name
FROM customer c
JOIN (
SELECT MAX(id) max_id, customer_id
FROM customer_data
GROUP BY customer_id
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MySQL case insensitive select
Can anyone tell me if a MySQL SELECT query is case sensitive or case insensitive by default? And if not, what query would I have to send so that I can do something like:
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Number of rows affected by an UPDATE in PL/SQL
... block, this can be achieved.
... If anyone has a solution to use it in a SELECT Command, I would be interested.
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jQuery get selected option value (not the text, but the attribute 'value')
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04/2020: Corrected old answer
Use :selected psuedo selector on the selected options and then use the .val function to get the value of the option.
$('select[name=selector] option').filter(':selected').val()
Side note: Using filter is better then using :sele...
How do I run Visual Studio as an administrator by default?
...indows 8, 8.1 and 10
In Windows 8, you have to right-click devenv.exe and select "Troubleshoot compatibility".
Select "Troubleshoot program"
Check "The program requires additional permissions"
click "Next", click "Test the program..."
Wait for the program to launch
Click "Next"
Select "Yes, save ...
LINQ query to select top five
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var list = (from t in ctn.Items
where t.DeliverySelection == true && t.Delivery.SentForDelivery == null
orderby t.Delivery.SubmissionDate
select t).Take(5);
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How do I get the current time zone of MySQL?
...bal and client-specific time zones can be retrieved like this:
mysql> SELECT @@global.time_zone, @@session.time_zone;
Edit The above returns SYSTEM if MySQL is set to slave to the system's timezone, which is less than helpful. Since you're using PHP, if the answer from MySQL is SYSTEM, you ca...
Correct way to use StringBuilder in SQL
...:
StringBuilder sb = new StringBuilder(some_appropriate_size);
sb.append("select id1, ");
sb.append(id2);
sb.append(" from ");
sb.append(table);
return sb.toString();
Note that I've listed some_appropriate_size in the StringBuilder constructor, so that it starts out with enough capacity for the f...