文件的内容(createdbtemplat1.sql)大致如下所示:
CREATE DATABASE mytemplate1 WITH ENCODING 'UTF8';
\c mytemplate1
CREATE TABLE first_table (
--- fields here ..
);
-- Add C language extension + functions
\i db_funcs.sql
希望能够编写一个shell脚本来执行文件中的命令:
# run commands to create TEMPLATE db mytemplate1
# ./groksqlcommands.sh createdbtemplate1.sql
for dbname in foo foofoo foobar barbar
do
# Need to simply create a database based on an existing template in this script
psql CREATE DATABASE $dbname TEMPLATE mytemplate1
done
可以试试这个:
>>> import array
>>> array
<module 'array' (built-in)>
>>> class A(array.array):
def __init__(self, *args):
super(array.array, self).__init__(*args)
print "init is fine for objects implemented in C"
>>> a=A('c')
init is fine for objects implemented in C
>>>
将看到相同的行为子类int、str等。
>>> import datetime
>>> class D(datetime.date):
def __new__(cls, year):
return datetime.date.__new__(cls, year, 1, 1)
>>> D(2008)
D(2008, 1, 1)