web.py Documentation, Release 0.37
The first argument is the table name and the rest of them are set of named arguments which represent the fields in the
table. If values are not given, the database may create default values or issue a warning.
For bulk insertion rather than inserting record by record, use Multiple Inserts rather.
2.2.2 Selecting
The select method is used for selecting rows from the database. It returns a web.iterbetter object, which can be looped
through.
To select all the rows from the user table, you would simply do
users = db.select('user')
For the real world use cases, select method takes vars, what, where, order, group, limit, offset, and _test optional
parameters.
users = db.select('users', where="id>100")
To prevent SQL injection attacks, you can use $key in where clause and pass the vars which has { ‘key’: value }.
vars = dict(name="Bob")
results = db.select('users', where="name = $name", vars=vars, _test=True)
>>> results
<sql: "SELECT
*
FROM users WHERE name = 'Bob'">
2.2.3 Updating
The update method accepts same kind of arguments as Select. It returns the number of rows updated.
num_updated = db.update('users', where="id = 10", firstname = "Foo")
2.2.4 Deleting
The delete method returns the number of rows deleted. It also accepts “using” and “vars” parameters. See
Selecting for more details on vars.
num_deleted = db.delete('users', where="id=10")
2.2.5 Multiple Inserts
The multiple_insert method on the db object allows you to do that. All that’s needed is to prepare a list of dictionaries,
one for each row to be inserted, each with the same set of keys and pass it to multiple_insert along with the table name.
It returns the list of ids of the inserted rows.
The value of db.supports_multiple_insert tells you if your database supports multiple inserts.
values = [{"name": "foo", "email": "foo@example.com"}, {"name": "bar", "email": "bar@example.com"}]
db.multiple_insert('person', values=values)
6 Chapter 2. Accessing the database
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