Mercurial Repository: p/roundup/code: roundup/backends/rdbms

comparison roundup/backends/rdbms_common.py @ 1479:405e91b5be46

fixed rdbms mutation of properties

author	Richard Jones <richard@users.sourceforge.net>
date	Thu, 27 Feb 2003 11:07:39 +0000
parents	5a01e90b7dc9
children	b3f2484babce

comparison

equal deleted inserted replaced

-:2ec91ead3add
+:405e91b5be46
-# $Id: rdbms_common.py,v 1.36 2003-02-26 23:42:54 richard Exp $
+# $Id: rdbms_common.py,v 1.37 2003-02-27 11:07:36 richard Exp $
 ''' Relational database (SQL) backend common code.
 Basics:
 - map roundup classes to relational tables
 else:
 cols.append('_'+col)
 cols.sort()
 return cols, mls
-def update_class(self, spec, dbspec):
+def update_class(self, spec, old_spec):
 ''' Determine the differences between the current spec and the
 database version of the spec, and update where necessary
 '''
-spec_schema = spec.schema()
+new_spec = spec
-if spec_schema == dbspec:
+new_has = new_spec.properties.has_key
-# no save needed for this one
+new_spec = new_spec.schema()
+if new_spec == old_spec:
+# no changes
 return 0
 if __debug__:
 print >>hyperdb.DEBUG, 'update_class FIRING'
 # key property changed?
-if dbspec[0] != spec_schema[0]:
+if old_spec[0] != new_spec[0]:
 if __debug__:
 print >>hyperdb.DEBUG, 'update_class setting keyprop', `spec[0]`
 # XXX turn on indexing for the key property
-# dict 'em up
+# detect multilinks that have been removed, and drop their table
-spec_propnames,spec_props = [],{}
+old_has = {}
-for propname,prop in spec_schema[1]:
+for name,prop in old_spec[1]:
-spec_propnames.append(propname)
+old_has[name] = 1
-spec_props[propname] = prop
+if not new_has(name) and isinstance(prop, Multilink):
-dbspec_propnames,dbspec_props = [],{}
+# it's a multilink, and it's been removed - drop the old
-for propname,prop in dbspec[1]:
+# table
-dbspec_propnames.append(propname)
-dbspec_props[propname] = prop
-# now compare
-for propname in spec_propnames:
-prop = spec_props[propname]
-if dbspec_props.has_key(propname) and prop==dbspec_props[propname]:
-continue
-if __debug__:
-print >>hyperdb.DEBUG, 'update_class ADD', (propname, prop)
-if not dbspec_props.has_key(propname):
-# add the property
-if isinstance(prop, Multilink):
-# all we have to do here is create a new table, easy!
-self.create_multilink_table(spec, propname)
-continue
-# no ALTER TABLE, so we:
-# 1. pull out the data, including an extra None column
-oldcols, x = self.determine_columns(dbspec[1])
-oldcols.append('id')
-oldcols.append('__retired__')
-cn = spec.classname
-sql = 'select %s,%s from _%s'%(','.join(oldcols), self.arg, cn)
-if __debug__:
-print >>hyperdb.DEBUG, 'update_class', (self, sql, None)
-self.cursor.execute(sql, (None,))
-olddata = self.cursor.fetchall()
-# 2. drop the old table
-self.cursor.execute('drop table _%s'%cn)
-# 3. create the new table
-cols, mls = self.create_class_table(spec)
-# ensure the new column is last
-cols.remove('_'+propname)
-assert oldcols == cols, "Column lists don't match!"
-cols.append('_'+propname)
-# 4. populate with the data from step one
-s = ','.join([self.arg for x in cols])
-scols = ','.join(cols)
-sql = 'insert into _%s (%s) values (%s)'%(cn, scols, s)
-# GAH, nothing had better go wrong from here on in... but
-# we have to commit the drop...
-# XXX this isn't necessary in sqlite :(
-self.conn.commit()
-# do the insert
-for row in olddata:
-self.sql(sql, tuple(row))
-else:
-# modify the property
-if __debug__:
-print >>hyperdb.DEBUG, 'update_class NOOP'
-pass  # NOOP in gadfly
-# and the other way - only worry about deletions here
-for propname in dbspec_propnames:
-prop = dbspec_props[propname]
-if spec_props.has_key(propname):
-continue
-if __debug__:
-print >>hyperdb.DEBUG, 'update_class REMOVE', `prop`
-# delete the property
-if isinstance(prop, Multilink):
 sql = 'drop table %s_%s'%(spec.classname, prop)
 if __debug__:
 print >>hyperdb.DEBUG, 'update_class', (self, sql)
 self.cursor.execute(sql)
-else:
+continue
-# no ALTER TABLE, so we:
+old_has = old_has.has_key
-# 1. pull out the data, excluding the removed column
-oldcols, x = self.determine_columns(spec.properties.items())
+# now figure how we populate the new table
-oldcols.append('id')
+fetch = []      # fetch these from the old table
-oldcols.append('__retired__')
+properties = spec.getprops()
-# remove the missing column
+for propname,x in new_spec[1]:
-oldcols.remove('_'+propname)
+prop = properties[propname]
-cn = spec.classname
+if isinstance(prop, Multilink):
-sql = 'select %s from _%s'%(','.join(oldcols), cn)
+if not old_has(propname):
-self.cursor.execute(sql, (None,))
+# we need to create the new table
-olddata = sql.fetchall()
+self.create_multilink_table(spec, propname)
+elif old_has(propname):
-# 2. drop the old table
+# we copy this col over from the old table
-self.cursor.execute('drop table _%s'%cn)
+fetch.append('_'+propname)
-# 3. create the new table
+# select the data out of the old table
-cols, mls = self.create_class_table(self, spec)
+fetch.append('id')
-assert oldcols != cols, "Column lists don't match!"
+fetch.append('__retired__')
+fetchcols = ','.join(fetch)
-# 4. populate with the data from step one
+cn = spec.classname
-qs = ','.join([self.arg for x in cols])
+sql = 'select %s from _%s'%(fetchcols, cn)
-sql = 'insert into _%s values (%s)'%(cn, s)
+if __debug__:
-self.cursor.execute(sql, olddata)
+print >>hyperdb.DEBUG, 'update_class', (self, sql)
+self.cursor.execute(sql)
+olddata = self.cursor.fetchall()
+# drop the old table
+self.cursor.execute('drop table _%s'%cn)
+# create the new table
+self.create_class_table(spec)
+if olddata:
+# do the insert
+args = ','.join([self.arg for x in fetch])
+sql = 'insert into _%s (%s) values (%s)'%(cn, fetchcols, args)
+if __debug__:
+print >>hyperdb.DEBUG, 'update_class', (self, sql, olddata[0])
+for entry in olddata:
+self.cursor.execute(sql, *entry)
 return 1
 def create_class_table(self, spec):
 ''' create the class table for the given spec
 '''

Mercurial > p > roundup > code

comparison roundup/backends/rdbms_common.py @ 1479:405e91b5be46