Archived:How to make an interactive SQL shell using PySymbian

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Created: cyke64 (31 Mar 2007)

Last edited: hamishwillee (31 May 2013)

To learn more easily the default SQL database you can make a small script to act as an interactive SQL shell in the command line interpreter !

First create the test db file with db.create(...). Then type in these lines below in the command line interpreter.

>>> import e32db
>>> db = e32db.Dbms()
>>> dbv = e32db.Db_view()
>>> db.open(u'C:\\test.db')

Here's the query simplification code.

def Q(sql):
    if sql.upper().startswith('SELECT'):
        dbv.prepare(db, unicode(sql))
        dbv.first_line()
        rows = []
        maxlen = [0] * dbv.col_count()
        for i in range(dbv.count_line()):
            dbv.get_line()
            result = []
            for i in range(dbv.col_count()):
                try:
                    val = dbv.col(i+1)
                except:    # in case coltype 16
                    val = None
                result.append(val)
                maxlen[i] = max(maxlen[i], len(str(val)))
            rows.append(result)
            dbv.next_line()
        fmt = '|'+ '|'.join(['%%%ds' % n for n in maxlen]) + '|'
        for row in rows:
            print fmt % tuple(row) 
    else:
        n = db.execute(unicode(sql))
        print '%d rows affected' % n

After that, playing with SQL is quite simple.

>>> Q("CREATE TABLE phone (id COUNTER, name VARCHAR, edition VARCHAR )")
0 rows affected
>>> Q("INSERT INTO phone (name,edition) VALUES ('N6600','2nd')")
1 rows affected
>>> Q("INSERT INTO phone (name,edition) VALUES ('N93','3rd')")
1 rows affected
>>> Q("SELECT * from phone")
|0|         6600|     2nd|
|1|          N93|     3rd|