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sqldict 0.5.2

sqldict - You have a dict of unlimited capacity providing transparent object serialization, its up to you now.

Welcome, please read through this brief documentation.

All the sqldict examples below will use an sqlalchemy engine e.
Certain database engines will need certain back-end modules
which in most cases are available as packages in your *nix
distribution or as .exe installers, see INSTALLATION* below.

Lets create the engine object:

>>> from sqlalchemy import *
>>> dburi = 'mysql://user:pass@localhost/sqldict'
>>> e = create_engine(dburi)

Create database tables, t1 and t2, to hold dicts d1 and d2:

>>> d1 = sqldict(e, "t1", create=1)
>>> d2 = sqldict(e, "t2", create=1, keytype=String(50), valtype=Integer)

An sqldict() support all or most common dict operations depending on
which sqldict extensions are chosen.

This is a selection of some useful sqldict instantiation args:

echo - print all executed sql queries to stdout (bool)
create - create database table (bool)
sort - 0=no sort, 1=keys, 2=values
serialize - transparent pickling for non-String type values
assigned to String-type columns (bool)
getrow - get entire row instead of just val (bool)
keycol - name of key column
valcol - name of val column
keytype - sqlalchemy column type for key
valtype - sqlalchemy column type for val

Actions taken such as setting/getting items result in logically
corresponding SQL statements. Some examples are:

__getitem__() - SELECT keycol FROM tablename WHERE valcol=%(val)s
iter*() - iterate over result-set from a select statement
keys|values() - returns list(iter*())
__del__() - DELETE FROM..
__setitem__() - UPDATE.., INSERT..

>>> contents = {"asd":123}
>>> d1.update(contents)
>>> d2.update(contents)
>>> assert d1["asd"] == "123"
>>> assert d2["asd"] == 123
>>> d1.drop()
>>> d2.drop()

>>> assert e.execute("create table asd (i integer, s varchar(50))")
>>> assert e.execute("insert into asd values (42, 'gubbe')")
>>> assert e.execute("insert into asd values (99, 'hatt')")
>>> d3 = sqldict(e, "asd", keycol="s", valcol="i")
>>> d4 = sqldict(e, "asd", keycol="i", valcol="s")
>>> #d5 = sqldict(e, "asd", keycol="s", valgetter=lambda r:r)
>>> assert d3["gubbe"] == 42
>>> assert d4[42] == "gubbe"
>>> assert e.execute("drop table asd")
>>> #assert d5["gubbe"]["i"] == 42

broken (at least mysql) when combining keytype and serialize,
it tries to serialize 42.
FIXME: d[int] = Integer or d[Integer]
>>> from sqlalchemy import *
>>> d = sqldict(e, "laarge", create=1, serialize=1, keytype=Integer)
>>> d[42] = "galning"


I use debian, so I do the following:
$ sudo apt-get install python-setuptools python-mysqldb
$ easy_install sqlalchemy
$ easy_install sqldict  
File Type Py Version Uploaded on Size
sqldict-0.5.2.tar.gz (md5) Source 2010-04-20 9KB