SQLAlchemy“ def print_usage（）”在Python 3中出现错误

Question

I'm following this link https://gist.github.com/thoas/1589496 that copies table from a database to a destination database.

I'm having error with this one

def print_usage():
    print """
Usage: %s -f source_server -t destination_server
    -f, -t = driver://user[:password]@host[:port]/database

Example: %s -f oracle://someuser:PaSsWd@db1/TSH1 \\
    -t mysql://root@db2:3307/reporting
    """ % (sys.argv[0], sys.argv[0])

in which I modify following the format for Python 3:

def print_usage():
    print("%s -f mysql://root@localhost:3306/db_test -t mysql://root@localhost:3306/db_test1" % (sys.argv[0], sys.argv[0]))

I wanted to test first in MySQL but there is an error

TypeError: not all arguments converted during string formatting

What is the problem on my string? Thanks!

Answer 1

you have only one %s in your format string while you have two variables to put in string.

more details:

when you do

print("%s -f mysql://root@localhost:3306/db_test -t mysql://root@localhost:3306/db_test1" % (sys.argv[0], sys.argv[0]))

you replace each '%s' with a value from (sys.argv[0], sys.argv[0]) so you must have the same number of '%s' and values in the tuple.

try change your code to this:

print("%s -f mysql://root@localhost:3306/db_test -t mysql://root@localhost:3306/db_test1" % (sys.argv[0], ))