On Thu, Jun 02, 2005 at 20:22:07 +0100, Mauro Delfino <[EMAIL PROTECTED]> wrote: > > I have the these two tables: > CREATE TABLE table_one > ( field1 VARCHAR(255) ); > > CREATE TABLE table_two > ( field1 VARCHAR(255) UNIQUE ); > > table_one has 500k records. I certify that all strings are distinct with > this query: > SELECT DISTINCT field1 FROM table_one; > The query results 500k rows. > > But if I try to insert the records of table_one into table_two with the > following command: > INSERT INTO table_two (field1) (SELECT field1 FROM table_one); > This error occurs: > ERROR: duplicate key violates unique constraint "table_two_field1_key" > > What happened? DISTINC and UNIQUE have different algorithms to determine > when two strings are equal?
Are you sure table_two is empty when you do this? ---------------------------(end of broadcast)--------------------------- TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]
