Jun 21, 2017

SQLite: Using a table to loop


You want to create a table with lots of records for testing purposes - in SQL you could make a loop using something like this:

while (@i <= 10000)
  insert into table1 values ( 'field1' + cast (@i as char).
 'field2'+ cast (@i as char).
set @i+=1

Unfortunately in SQlite loops are not implemented - but you could use this trick instead
It will use a tIndex table, and a tRange table to generate some records in a tTarget table.

The tTarget table  is for the result:
create table target (i text);

This table will receive the result as text

tRange table

create table tRange (start, finish);
insert into tRange (1, 100) ;

And then afterward you can change the start and finish parameters using:
update tRange set start = 3 ;
update tRange set finish = 90 ;

tIndex table

This one is tricky because it has to contain as many records as possible - you will have to create this table via a Java program (see previous post) - by default there will be 10,000 records.

Now the Loop trick 

insert into tTarget(i)
select ('Record number '||tIndex.id)
from tIndex join tRange
on (tIndex.id >= tRange.start and tIndex.id <= tRange.finish) ;

This will generate Record Number + start ...  up to Record Number+ finish

Java: Creating a table with 10,000 records in SQLite

May 31, 2017

Linux: xfce panel setings (advanced)

Windows Buttons panel settings

Nothing special here

Separator settings

This particular settings on the separator will prevent the "windows buttons" and the next notifications settings on the panel bar to move around while the other one expand - (since the Windows buttons item will inevitably grow during the session activity)

By ticking "expand" on the separator you are making sure - the "windows Button" item behavior will not impact the rest of the items on the panel

Indicator settings

Just standard - nothing special either


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