Hi,

> select * from csvread('secfile.csv') b  inner join
> csvread(firstfile.csv') a on b.col1=a.col1 order by a.col1

This will read the file 'secfile.csv' once, but the file
'firstfile.csv' is read once _for every row_ in the other file.

For performance reason, CSVREAD</code> should not be used inside a
join. Instead, import the data first (possibly into a temporary
table), create the required indexes if necessary, and then query this
table. Here, you should create an index on the column col1 (for both
tables).

For how to do import a table from a CSV file, see:
http://h2database.com/html/tutorial.html#csv

Regards,
Thomas

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