Hi Akbar,
What you are looking are trigers.
CREATE TRIGGER <triger_name> BEFORE INSERT OR UPDATE
ON <table_name> FOR EACH ROW EXECUTE PROCEDURE
<function_name>(<function params>);
To find out how to write functions, which can be used in triger, read
the documentation.
Kaloyan
Akbar wrote:
> Hi, I have table which has two column ( column a & b ). One of the
> column has type string..... that is column_a.
> Assume somebody insert this value to my table:
> INSERT INTO my_table ( column_a ) VALUES ( ' Bla bla bla ' );
>
> I want that string value ( ' Bla bla bla ' ) to be lowered
> before insert into my table and remove unnecessary space. So the value
> will be 'bla bla bla'. The space is just one. There will be no space
> in front and back of the string. I don't want double space between
> word too. How do I accomplish that?????
>
> This is my best effort:
> CREATE RULE string_insert AS ON INSERT TO my_table
> DO UPDATE my_table SET column_a =
> lower(column_a);
>
> However this way is not efficient because it will update all row. I
> just want to update only row which has just been inserted into table.
> And how do you remove the double space between words? I know there is
> function trim to remove leading and trailing space. But space more
> than one between two words?????
>
> Thank you.
>
> Regards,
>
> Akbar
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 7: don't forget to increase your free space map settings
>
>