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How do you find the disk size of a Postgres / PostgreSQL table and its indexes
I'm coming to Postgres from Oracle and looking for a way to find the table and index size in terms of bytes/MB/GB/etc , or even better the size for all tables. In Oracle I had a nasty long query that looked at user_lobs and user_segments to give back an answer.
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Advantages of Binary Search Trees over Hash Tables
What are the advantages of binary search trees over hash tables?
18 Answers
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jquery - fastest way to remove all rows from a very large table
I thought this might be a fast way to remove the contents of a very large table (3000 rows):
8 Answers
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How to list of all the tables defined for the database when using active record?
How do I get a list of all the tables defined for the database when using active record?
5 Answers
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CROSS JOIN vs INNER JOIN in SQL
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Cross join does not combine the rows, if you have 100 rows in each table with 1 to 1 match, you get 10.000 results, Innerjoin will only return 100 rows in the same situation.
These 2 examples will return the same result:
Cross join
select * from table1 cross join table2 where table1.id = ...
What is the difference between “INNER JOIN” and “OUTER JOIN”?
... the outer parts of a Venn diagram union.
Examples
Suppose you have two tables, with a single column each, and data as follows:
A B
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1 3
2 4
3 5
4 6
Note that (1,2) are unique to A, (3,4) are common, and (5,6) are unique to B.
Inner join
An inner join using either of the...
Search of table names
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I'm using this and works fine
SELECT * FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_NAME LIKE '%%'
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Fixed Table Cell Width
A lot of people still use tables to layout controls, data etc. - one example of this is the popular jqGrid. However, there is some magic happening that I cant seem to fathom (its tables for crying out loud, how much magic could there possibly be?)
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How to insert a SQLite record with a datetime set to 'now' in Android application?
Say, we have a table created as:
10 Answers
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MySql export schema without data
...nsider using the --single-transaction option if you don't want or can't do table locks.
– Jim
Jan 22 '13 at 21:55
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