Tuples Are Not Inserted Sequentially in Database Table

Tuples are not inserted sequentially in database table?

This is a misunderstanding. There is no "natural" order in a relational database table. While rows are normally inserted in sequence to the physical file holding a table, a wide range of activities can reshuffle physical order. And queries doing anything more than a basic (non-parallelized) sequential scan may return rows in any opportune order. That's according to standard SQL.

The order you see is arbitrary unless you add ORDER BY to the query.

pgAdmin3 by default orders rows by the primary key (unless specified otherwise). Your column is of type varchar and rows are ordered alphabetically (according to your current locale). All by design, all as it should be.

To sort rows like you seem to be expecting, you could pad some '0' in your text:

...
typename_0009
typename_0010
...

The proper solution would be to have a numeric column with just the number, though.

You may be interested in natural-sort. You may also be interested in a serial column.

How to display all rows based on column frequency PostgreSQL

One way is to add the count per customer with a window function in a subquery, and then order by that.

SELECT customer, product
FROM  (
   SELECT customer, product
        , count(*) OVER (PARTITION BY customer) AS ct
   FROM   tbl
   ) sub
ORDER  BY ct DESC, customer, product;

Since multiple customer may have the same number of products, add more ORDER BY expressions to get a deterministic sort order.

How to make multiple slightly different inserts fast from PHP

Are your inserts being executed in a mysql transaction? If not, this might help improve performance for you.

http://kevin.vanzonneveld.net/techblog/article/improve_mysql_insert_performance/

inserting rows from one table to another, which sql is more efficient (outer join vs sequential scan)

I think option B is better, especially if Table A is bigger than Table B by a factor > 1.

If you have indexes on a.id and b.id then joining will be faster, IMHO, than using where for each row...

Howto set sequence as default value via pgAdmin?

Got it. Have a look here: http://pgadmin.org/docs/1.4/pg/functions-sequence.html The sequence name has to be quoted like this nextval('"primaryKeySequence"') because it is not lowercase

pgAdmin III Why query results are shortened?

Thanks to user Erwin Brandstetter for his answer on Database Administrators.

There is a setting for that in the options: Max characters per column - useful when dealing with big columns. Obviously your setting is 256 characters.

Set it higher or set it to -1 to disable the feature.

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