Python Script to Generate MySQL Stored Routines

Question

Here is a quick Python script that reads a MySQL scheme (database) and for each table, it generates Insert, Update, Get and Delete stored routines.  The script is just a "quick-n-dirty" script, but it does take into account that the Update, Get and Delete routines need to key off the primary key (and if there's not one, there could be trouble!).  Each stored routine is output into a separate file.
I'm attaching the script so you professional Python people can tell me where I could improve the script with respect to simplicity, readability, cleanliness, etc.
I have NOT yet got the command line parameters added to this script, but plan to soon.
#!/usr/bin/env python
# spgen.py
# Copyright 2008 Matt Runion <[email protected]>
import sys
import MySQLdb
# The INSERT template
insertTemplate = """
DELIMITER $$
DROP PROCEDURE IF EXISTS `%s`$$
CREATE PROCEDURE `%s` (%s)
BEGIN
INSERT INTO %s (
%s
) VALUES (
%s
END$$
DELIMITER ;
# The UPDATE template
updateTemplate = """
DELIMITER $$
DROP PROCEDURE IF EXISTS `%s`$$
CREATE PROCEDURE `%s` (%s)
BEGIN
UPDATE %s SET
%s
WHERE
%s;
END$$
DELIMITER ;
# The GET template
getTemplate = """
DELIMITER $$
DROP PROCEDURE IF EXISTS `%s`$$
CREATE PROCEDURE `%s` (%s)
BEGIN
SELECT
%s
FROM %s
WHERE
%s;
END$$
DELIMITER ;
# The DELETE template
deleteTemplate = """
DELIMITER $$
DROP PROCEDURE IF EXISTS `%s`$$
CREATE PROCEDURE `%s` (%s)
BEGIN
DELETE FROM %s
WHERE
%s;
END$$
DELIMITER ;
def generateSPs(dbhost, dbname, dbuser, dbpasswd):
This method reads all the tables from the database and for each of them
generates the following stored routines:
<TableName>_Insert
<TableName>_Update
<TableName>_Get
<TableName>_Delete
# Open the database connection
print 'Connecting to database [%s] on host [%s]' % (dbname, dbhost)
dbConn = MySQLdb.connect(host=dbhost, user=dbuser, passwd=dbpasswd, db=dbname)
cur = dbConn.cursor()
# Get a list of all tables in the database
print 'Reading tables...'
cur.execute("SHOW TABLES FROM %s" % dbname)
tables = cur.fetchall()
for table in tables:
print 'Generating stored procs for table [%s]...' % table[0]
# Get a list of a columns in the current table
cur.execute("SHOW COLUMNS FROM %s" % table[0])
columns = cur.fetchall()
insertUpdateParms = ''
getDeleteParms = ''
whereClause = ''
insertList = ''
valuesList = ''
updateList = ''
for column in columns:
# Reset some variables
print ' %s -- %s [%s, %s, %s]' % (column[0], column[1], column[2], column[3], column[4])
# Append the columns to the input parms
if (len(insertUpdateParms) > 0):
insertUpdateParms += ',\n'
insertList += ',\n'
valuesList += ',\n'
if (len(updateList) > 0):
updateList += ',\n'
insertUpdateParms += '%sIN ' % column[0]
if ((column[1][0:3].lower() == 'var') or (column[1][0:3].lower() == 'cha')):
insertUpdateParms += '%s' % column[1]
elif (column[1][0:3].lower() == 'enu'):
insertUpdateParms += 'varchar(50)'
else:
insertUpdateParms += (column[1].split('('))[0]
insertList += column[0]
valuesList += '%sIN' % column[0]
# Generate the key parms that are used for the Get and Delete
# stored procs, and generate the values for the WHERE clause
# for the Update, Get and Delete stored procs
if (column[3].lower() == 'pri'):
if (len(getDeleteParms) > 0):
getDeleteParms += ',\n'
getDeleteParms += '%sIN ' % column[0]
if (column[1][0:3].lower() == 'var'):
getDeleteParms += '%s' % column[1]
else:
getDeleteParms += (column[1].split('('))[0]
if (len(whereClause) > 0):
whereClause += ' AND \n'
whereClause += '%s = %sIN' % (column[0], column[0])
else:
updateList += '%s = %sIN' % (column[0], column[0])
#print '---'
#print insertUpdateParms
#print '---'
#print getDeleteParms
#print '---'
#print whereClause
#print 'INSERT:'
#print insertTemplate % (table[0] + '_Insert', table[0] + '_Insert', insertUpdateParms, table[0], insertList, valuesList)
#print 'UPDATE:'
#print updateTemplate % (table[0] + '_Update', table[0] + '_Update', insertUpdateParms, table[0], updateList, whereClause)
#print 'GET:'
#print getTemplate % (table[0] + '_Get', table[0] + '_Get', getDeleteParms, insertList, table[0], whereClause)
#print 'DELETE:'
#print deleteTemplate % (table[0] + '_Delete', table[0] + '_Delete', getDeleteParms, table[0], whereClause)
# Write out the INSERT stored proc
file = open('./test/' + table[0] + '_Insert', 'w')
file.write(insertTemplate % (table[0] + '_Insert', table[0] + '_Insert', insertUpdateParms, table[0], insertList, valuesList))
file.close()
# Write out the UPDATE stored proc
file = open('./test/' + table[0] + '_Update', 'w')
file.write(updateTemplate % (table[0] + '_Update', table[0] + '_Update', insertUpdateParms, table[0], updateList, whereClause))
file.close()
# Write out the GET stored proc
file = open('./test/' + table[0] + '_Get', 'w')
file.write(getTemplate % (table[0] + '_Get', table[0] + '_Get', getDeleteParms, insertList, table[0], whereClause))
file.close()
# Write out the DELETE stored proc
file = open('./test/' + table[0] + '_Delete', 'w')
file.write(deleteTemplate % (table[0] + '_Delete', table[0] + '_Delete', getDeleteParms, table[0], whereClause))
file.close()
return 0
if __name__ == '__main__':
generateSPs('<SERVER>', '<DATABASE>', '<USER>', '<PASSWD>')

Answer 1

I found and fixed a bug with some misplaced parenthesis that forced the path to be made all lower-case.  This was a bad thing if the path had some upper case letters in it!
#!/usr/bin/env python
# spgen.py
# Copyright 2008 Matt Runion <[email protected]>
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
# MA 02110-1301, USA.
import sys
import getopt
import os
import MySQLdb
# The INSERT template
insertTemplate = """
DELIMITER $$
DROP PROCEDURE IF EXISTS `%s`$$
CREATE PROCEDURE `%s` (%s)
BEGIN
INSERT INTO %s (
%s
) VALUES (
%s
END$$
DELIMITER ;
# The UPDATE template
updateTemplate = """
DELIMITER $$
DROP PROCEDURE IF EXISTS `%s`$$
CREATE PROCEDURE `%s` (%s)
BEGIN
UPDATE %s SET
%s
WHERE
%s;
END$$
DELIMITER ;
# The GET template
getTemplate = """
DELIMITER $$
DROP PROCEDURE IF EXISTS `%s`$$
CREATE PROCEDURE `%s` (%s)
BEGIN
SELECT
%s
FROM %s
WHERE
%s;
END$$
DELIMITER ;
# The DELETE template
deleteTemplate = """
DELIMITER $$
DROP PROCEDURE IF EXISTS `%s`$$
CREATE PROCEDURE `%s` (%s)
BEGIN
DELETE FROM %s
WHERE
%s;
END$$
DELIMITER ;
def generateSPs(dbhost, dbname, dbuser, dbpasswd, outPath):
This method reads all the tables from the database and for each of them
generates the following stored routines:
<TableName>_Insert
<TableName>_Update
<TableName>_Get
<TableName>_Delete
# Open the database connection
print 'Connecting to database [%s] on host [%s]' % (dbname, dbhost)
dbConn = MySQLdb.connect(host=dbhost, user=dbuser, passwd=dbpasswd, db=dbname)
cur = dbConn.cursor()
# Get a list of all tables in the database
print 'Reading tables...'
cur.execute("SHOW TABLES FROM %s" % dbname)
tables = cur.fetchall()
for table in tables:
print 'Generating stored procs for table [%s]...' % table[0]
# Get a list of a columns in the current table
cur.execute("SHOW COLUMNS FROM %s" % table[0])
columns = cur.fetchall()
insertUpdateParms = ''
getDeleteParms = ''
whereClause = ''
insertList = ''
valuesList = ''
updateList = ''
for column in columns:
# Reset some variables
print ' %s -- %s [%s, %s, %s]' % (column[0], column[1], column[2], column[3], column[4])
# Append the columns to the input parms
if (len(insertUpdateParms) > 0):
insertUpdateParms += ',\n'
insertList += ',\n'
valuesList += ',\n'
if (len(updateList) > 0):
updateList += ',\n'
insertUpdateParms += '%sIN ' % column[0]
if ((column[1][0:3].lower() == 'var') or (column[1][0:3].lower() == 'cha')):
insertUpdateParms += '%s' % column[1]
elif (column[1][0:3].lower() == 'enu'):
insertUpdateParms += 'varchar(50)'
else:
insertUpdateParms += (column[1].split('('))[0]
insertList += column[0]
valuesList += '%sIN' % column[0]
# Generate the key parms that are used for the Get and Delete
# stored procs, and generate the values for the WHERE clause
# for the Update, Get and Delete stored procs
if (column[3].lower() == 'pri'):
if (len(getDeleteParms) > 0):
getDeleteParms += ',\n'
getDeleteParms += '%sIN ' % column[0]
if (column[1][0:3].lower() == 'var'):
getDeleteParms += '%s' % column[1]
else:
getDeleteParms += (column[1].split('('))[0]
if (len(whereClause) > 0):
whereClause += ' AND \n'
whereClause += '%s = %sIN' % (column[0], column[0])
else:
updateList += '%s = %sIN' % (column[0], column[0])
# Write out the INSERT stored proc
file = open(os.path.join(outPath,(table[0] + '_Insert.sql').lower()), 'w')
file.write(insertTemplate % (table[0] + '_Insert', table[0] + '_Insert', insertUpdateParms, table[0], insertList, valuesList))
file.close()
# Write out the UPDATE stored proc
file = open(os.path.join(outPath,(table[0] + '_Update.sql').lower()), 'w')
file.write(updateTemplate % (table[0] + '_Update', table[0] + '_Update', insertUpdateParms, table[0], updateList, whereClause))
file.close()
# Write out the GET stored proc
file = open(os.path.join(outPath,(table[0] + '_Get.sql').lower()), 'w')
file.write(getTemplate % (table[0] + '_Get', table[0] + '_Get', getDeleteParms, insertList, table[0], whereClause))
file.close()
# Write out the DELETE stored proc
file = open(os.path.join(outPath,(table[0] + '_Delete.sql').lower()), 'w')
file.write(deleteTemplate % (table[0] + '_Delete', table[0] + '_Delete', getDeleteParms, table[0], whereClause))
file.close()
return 0
def main(argv):
SPGen reads all the tables from the given database and for each of
those tables generates the following stored routines:
<TableName>_Insert
<TableName>_Update
<TableName>_Get
<TableName>_Delete
Command line arguments are:
-?, --help: Help
-o, --outputpath: File output path
-h, --host: Database host/server
-d, --database: Database name
-u, --user: Database user
-p, --password Database password
# Set defaults...
outputPath = os.getcwd()
host = 'localhost'
database = ''
user = ''
password = ''
# See what command line options we have
try:
opts, args = getopt.getopt(argv[1:], '?o:h:d:u:p:', ['help', 'outputpath=', 'host=', 'database=', 'user=', 'password='])
except getopt.GetoptError:
print main.__doc__
sys.exit(2)
for opt, arg in opts:
if opt in ['-?', '--help']:
print main.__doc__
sys.exit()
elif opt in ['-o', '--outputpath']:
outputPath = arg
elif opt in ['-h', '--host']:
host = arg
elif opt in ['-d', '--database']:
database = arg
elif opt in ['-u', '--user']:
user = arg
elif opt in ['-p', '--password']:
password = arg
generateSPs(dbhost=host, dbname=database, dbuser=user, dbpasswd=password, outPath=outputPath)
if __name__ == '__main__':
main(sys.argv)
Last edited by mrunion (2008-11-20 19:33:37)