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Import CSV to SQLite
I'm trying to import a csv file to an SQLite table.
10 Answers
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Insert, on duplicate update in PostgreSQL?
...LICT clause. with the following syntax (similar to MySQL)
INSERT INTO the_table (id, column_1, column_2)
VALUES (1, 'A', 'X'), (2, 'B', 'Y'), (3, 'C', 'Z')
ON CONFLICT (id) DO UPDATE
SET column_1 = excluded.column_1,
column_2 = excluded.column_2;
Searching postgresql's email group ar...
JOIN queries vs multiple queries
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if you are joining 3 or more tables on different keys, often databases (i.e. mysql) can only use one index per table, meaning maybe one of the joins will be fast (and use an index) whereas the others will be extremely slow. For multiple queries, you can ...
In C/C++ what's the simplest way to reverse the order of bits in a byte?
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If you are talking about a single byte, a table-lookup is probably the best bet, unless for some reason you don't have 256 bytes available.
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How to pass table value parameters to stored procedure from .net code
I have a SQL Server 2005 database. In a few procedures I have table parameters that I pass to a stored proc as an nvarchar (separated by commas) and internally divide into single values. I add it to the SQL command parameters list like this:
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Importance of varchar length in MySQL table
I have a MySQL table where rows are inserted dynamically. Because I can not be certain of the length of strings and do not want them cut off, I make them varchar(200) which is generally much bigger than I need. Is there a big performance hit in giving a varchar field much more length than necessar...
How to delete all the rows in a table using Eloquent?
... for Laravel 4 and 5:
MyModel::truncate();
That drops all rows from the table without logging individual row deletions.
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MySQL JOIN the most recent row only?
I have a table customer that stores a customer_id, email and reference. There is an additional table customer_data that stores a historical record of the changes made to the customer, i.e. when there's a change made a new row is inserted.
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Database design for audit logging
... an idea of what the old record looked like.
So for example, if you had a table called Opportunities to track sales deals, you would actually create two separate tables:
Opportunities
Opportunities_Content (or something like that)
The Opportunities table would have information you'd use to unique...
How to request a random row in SQL?
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See this post: SQL to Select a random row from a database table. It goes through methods for doing this in MySQL, PostgreSQL, Microsoft SQL Server, IBM DB2 and Oracle (the following is copied from that link):
Select a random row with MySQL:
SELECT column FROM table
ORDER BY RAND()...