sqlite3 - SQL question regarding update of a table based on lookup table

[Gugyu]

I have a table AVI with the following relevant structure:
POLY_NUM key
LKP
SITE1
SITE2
SITE3
Y2BH

I have a lookup table SILKP with:
LKP
SITE1
SITE2
SITE3
Y2BH

what is the fastest/most efficient way to update table A SITE1-SITE3 and Y2BH fields by linking via lookup.

What I have:

with sqlite3.connect(db_filename) as conn:
    cursor = conn.cursor()

    print "Updating lookup fields..."
    
    cursor.execute("""
                        UPDATE avi SET site1 = (SELECT site1 FROM silkp WHERE silkp.lkp = avi.lkp)
                   """)
    cursor.execute("""
                        UPDATE avi SET site2 = (SELECT site2 FROM silkp WHERE silkp.lkp = avi.lkp)
                   """)
    cursor.execute("""
                        UPDATE avi SET site3 = (SELECT site3 FROM silkp WHERE silkp.lkp = avi.lkp)
                   """)
                        UPDATE avi SET y2bh = (SELECT y2bh FROM silkp WHERE silkp.lkp = avi.lkp)
                   """)

Is there a faster and more elegant way?

[Rabbit]

You can try joining the tables and updating it in one statement. This works in SQL Server, you can see if it works in SQLite.

UPDATE t1
SET field1 = t2.field1,
    field2 = t2.field2
FROM t1 INNER JOIN 
     t2 ON t1.id = t2.id