Skip to content

Commit

Permalink
Updated raw sqls to use 'select for update' query.
Browse files Browse the repository at this point in the history
  • Loading branch information
@1Arpit
1Arpit committed Dec 11, 2015
1 parent c2aa6a2 commit ea00205
Showing 1 changed file with 62 additions and 44 deletions.
106 changes: 62 additions & 44 deletions treebeard/ns_tree.py
View file
Original file line number Diff line number Diff line change
Expand Up @@ -143,8 +143,8 @@ def add_root(cls, **kwargs):
# adding the passed (unsaved) instance to the tree
newobj = kwargs['instance']
if newobj.pk:
raise NodeAlreadySaved("Attempted to add a tree node that is "\
"already in the database")
raise NodeAlreadySaved("Attempted to add a tree node that is "
"already in the database")
else:
# creating the new object
newobj = get_result_class(cls)(**kwargs)
Expand All @@ -163,31 +163,38 @@ def _move_right(cls, tree_id, rgt, lftmove=False, incdec=2):
lftop = '>='
else:
lftop = '>'
sql = 'UPDATE %(table)s '\
' SET lft = CASE WHEN lft %(lftop)s %(parent_rgt)d '\
' THEN lft %(incdec)+d '\
' ELSE lft END, '\
' rgt = CASE WHEN rgt >= %(parent_rgt)d '\
' THEN rgt %(incdec)+d '\
' ELSE rgt END '\
' WHERE rgt >= %(parent_rgt)d AND '\
' tree_id = %(tree_id)s' % {
'table': connection.ops.quote_name(
get_result_class(cls)._meta.db_table),
sql = 'BEGIN ;' \
' SELECT lft, rgt FROM %(table)s WHERE rgt >= %(parent_rgt)d ' \
' AND tree_id = %(tree_id)s FOR UPDATE;' \
' UPDATE %(table)s ' \
' SET lft = CASE WHEN lft %(lftop)s %(parent_rgt)d ' \
' THEN lft %(incdec)+d ' \
' ELSE lft END, ' \
' rgt = CASE WHEN rgt >= %(parent_rgt)d ' \
' THEN rgt %(incdec)+d ' \
' ELSE rgt END ' \
' WHERE rgt >= %(parent_rgt)d AND ' \
' tree_id = %(tree_id)s ;' \
'END;' % {
'table': connection.ops.quote_name(cls._meta.db_table),
'parent_rgt': rgt,
'tree_id': tree_id,
'lftop': lftop,
'incdec': incdec}
'incdec': incdec
}
return sql, []

@classmethod
def _move_tree_right(cls, tree_id):
sql = 'UPDATE %(table)s '\
' SET tree_id = tree_id+1 '\
' WHERE tree_id >= %(tree_id)d' % {
'table': connection.ops.quote_name(
get_result_class(cls)._meta.db_table),
'tree_id': tree_id}
sql = 'BEGIN ;' \
' SELECT tree_id FROM %(table)s WHERE tree_id >= %(tree_id)d FOR UPDATE;' \
' UPDATE %(table)s ' \
' SET tree_id = tree_id+1 ' \
' WHERE tree_id >= %(tree_id)d ;' \
'END;' % {
'table': connection.ops.quote_name(cls._meta.db_table),
'tree_id': tree_id
}
return sql, []

def add_child(self, **kwargs):
Expand Down Expand Up @@ -444,47 +451,58 @@ def move(self, target, pos=None):
depthdiff += 1

# move the tree to the hole
sql = "UPDATE %(table)s "\
" SET tree_id = %(target_tree)d, "\
" lft = lft + %(jump)d , "\
" rgt = rgt + %(jump)d , "\
" depth = depth + %(depthdiff)d "\
" WHERE tree_id = %(from_tree)d AND "\
" lft BETWEEN %(fromlft)d AND %(fromrgt)d" % {
sql = "BEGIN;" \
" SELECT tree_id, lft, rgt, depth FROM %(table)s " \
" WHERE tree_id = %(from_tree)d AND " \
" lft BETWEEN %(fromlft)d AND %(fromrgt)d " \
" FOR UPDATE;" \
" UPDATE %(table)s " \
" SET tree_id = %(target_tree)d, " \
" lft = lft + %(jump)d , " \
" rgt = rgt + %(jump)d , " \
" depth = depth + %(depthdiff)d " \
" WHERE tree_id = %(from_tree)d AND " \
" lft BETWEEN %(fromlft)d AND %(fromrgt)d ;" \
"END;" % {
'table': connection.ops.quote_name(cls._meta.db_table),
'from_tree': fromobj.tree_id,
'target_tree': target_tree,
'jump': newpos - fromobj.lft,
'depthdiff': depthdiff,
'fromlft': fromobj.lft,
'fromrgt': fromobj.rgt}
'fromrgt': fromobj.rgt
}
cursor.execute(sql, [])

# close the gap
sql, params = cls._get_close_gap_sql(fromobj.lft,
fromobj.rgt, fromobj.tree_id)
cursor.execute(sql, params)


@classmethod
def _get_close_gap_sql(cls, drop_lft, drop_rgt, tree_id):
sql = 'UPDATE %(table)s '\
' SET lft = CASE '\
' WHEN lft > %(drop_lft)d '\
' THEN lft - %(gapsize)d '\
' ELSE lft END, '\
' rgt = CASE '\
' WHEN rgt > %(drop_lft)d '\
' THEN rgt - %(gapsize)d '\
' ELSE rgt END '\
' WHERE (lft > %(drop_lft)d '\
' OR rgt > %(drop_lft)d) AND '\
' tree_id=%(tree_id)d' % {
'table': connection.ops.quote_name(
get_result_class(cls)._meta.db_table),
sql = 'BEGIN ;' \
' SELECT lft, rgt FROM %(table)s WHERE ' \
' (lft > %(drop_lft)d OR rgt > %(drop_lft)d) ' \
' AND tree_id=%(tree_id)d ' \
' FOR UPDATE;' \
' UPDATE %(table)s ' \
' SET lft = CASE ' \
' WHEN lft > %(drop_lft)d ' \
' THEN lft - %(gapsize)d ' \
' ELSE lft END, ' \
' rgt = CASE ' \
' WHEN rgt > %(drop_lft)d ' \
' THEN rgt - %(gapsize)d ' \
' ELSE rgt END ' \
' WHERE (lft > %(drop_lft)d OR rgt > %(drop_lft)d) ' \
' AND tree_id=%(tree_id)d;' \
'END ' % {
'table': connection.ops.quote_name(cls._meta.db_table),
'gapsize': drop_rgt - drop_lft + 1,
'drop_lft': drop_lft,
'tree_id': tree_id}
'tree_id': tree_id
}
return sql, []

@classmethod
Expand Down

0 comments on commit ea00205

Please sign in to comment.