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Inner join vs Where
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No! The same execution plan, look at these two tables:
CREATE TABLE table1 (
id INT,
name VARCHAR(20)
);
CREATE TABLE table2 (
id INT,
name VARCHAR(20)
);
The execution plan for the query using the inner join:
-- with inner join
EXPLAIN PLAN FOR
SELECT * FRO...
When to use a View instead of a Table?
When should a View actually be used over an actual Table? What gains should I expect this to produce?
8 Answers
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How to copy from CSV file to PostgreSQL table with headers in CSV file?
I want to copy a CSV file to a Postgres table. There are about 100 columns in this table, so I do not want to rewrite them if I don't have to.
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How to write DataFrame to postgres table?
...te_engine('postgresql://scott:tiger@localhost:5432/mydatabase')
df.to_sql('table_name', engine)
You are correct that in pandas up to version 0.13.1 postgresql was not supported. If you need to use an older version of pandas, here is a patched version of pandas.io.sql: https://gist.github.com/jor...
Best design for a changelog / auditing database table? [closed]
I need to create a database table to store different change log/auditing
(when something was added, deleted, modified, etc). I don't need to store particularly detailed info, so I was thinking something along the lines of:
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How to fix height of TR?
Is it possible to fix the height of a row (tr) on a table?
7 Answers
7
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Delete all rows in an HTML table
How can I delete all rows of an HTML table except the <th> 's using Javascript, and without looping through all the rows in the table? I have a very huge table and I don't want to freeze the UI while I'm looping through the rows to delete them
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MySQL Cannot drop index needed in a foreign key constraint
...e foreign key. Foreign keys in MySQL automatically create an index on the table (There was a SO Question on the topic).
ALTER TABLE mytable DROP FOREIGN KEY mytable_ibfk_1 ;
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SQL Server add auto increment primary key to existing table
As the title, I have an existing table which is already populated with 150000 records. I have added an Id column (which is currently null).
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Error 1022 - Can't write; duplicate key in table
I'm getting a 1022 error regarding duplicate keys on create table command. Having looked at the query, I can't understand where the duplication is taking place. Can anyone else see it?
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