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How to select all records from one table that do not exist in another table?
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SELECT t1.name
FROM table1 t1
LEFT JOIN table2 t2 ON t2.name = t1.name
WHERE t2.name IS NULL
Q: What is happening here?
A: Conceptually, we select all rows from table1 and for each row we attempt to find a row in table2 with the same value fo...
Align image in center and middle within div
...lute; width:100%; height:100%"> <img src="img8a.flixcart.com/image/tablet/f/k/t/…"> </div> </body> </html>
– nizam.sp
Oct 21 '13 at 11:00
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How to get a list of MySQL views?
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SHOW FULL TABLES IN database_name WHERE TABLE_TYPE LIKE 'VIEW';
MySQL query to find all views in a database
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How to design a product table for many kinds of product where each product has many parameters
I do not have much experience in table design. My goal is to create one or more product tables that meet the requirements below:
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Rounded table corners CSS only
...Q/3/
Edit: Here's a relatively clean implementation of your sketch:
table {
border-collapse:separate;
border:solid black 1px;
border-radius:6px;
-moz-border-radius:6px;
}
td, th {
border-left:solid black 1px;
border-top:solid black 1px;
}
th {
backgr...
Repair all tables in one go
How to check all the tables in the database in one go?
10 Answers
10
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How do I temporarily disable triggers in PostgreSQL?
...ly, if you are wanting to disable all triggers, not just those on the USER table, you can use:
SET session_replication_role = replica;
This disables triggers for the current session.
To re-enable for the same session:
SET session_replication_role = DEFAULT;
Source: http://koo.fi/blog/2013/01...
Can you have if-then-else logic in SQL? [duplicate]
I need to do select data from a table based on some kind of priority like so:
7 Answers
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Convert column classes in data.table
I have a problem using data.table: How do I convert column classes? Here is a simple example: With data.frame I don't have a problem converting it, with data.table I just don't know how:
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Does pandas iterrows have performance issues?
...ache-friendly and thus very fast. A pandas DataFrame is a "column-oriented table", which means that each column is really just an array. So the native actions you can perform on a DataFrame (like summing all the elements in a column) are going to have few cache misses.
More opportunities for paralle...