X-Git-Url: https://git.decadent.org.uk/gitweb/?a=blobdiff_plain;f=daklib%2Fdaksql.py;fp=daklib%2Fdaksql.py;h=d2fe6b89d0a6346612fe3f80dfb179083ced24bc;hb=c3b0c290fd49f8d82f2671aa57b034d97ad6cb4c;hp=0000000000000000000000000000000000000000;hpb=c3e9297611df02c1c8edd3d2ca8d676932009580;p=dak.git diff --git a/daklib/daksql.py b/daklib/daksql.py new file mode 100644 index 00000000..d2fe6b89 --- /dev/null +++ b/daklib/daksql.py @@ -0,0 +1,52 @@ +"""SQLAlchemy extensions for dak + +@copyright: 2014, Ansgar Burchardt +@license: GPL-2+ +""" + +# 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + +from sqlalchemy.ext.compiler import compiles +from sqlalchemy.sql.expression import ColumnElement, ClauseElement, ClauseList, literal +from sqlalchemy.types import Text +from sqlalchemy.util import to_list + +class array_agg(ColumnElement): + def __init__(self, expr, order_by=None): + self.expr = ClauseElement(expr) + self.order_by = None + if order_by is not None: + self.order_by = ClauseList(*to_list(order_by)) + +@compiles(array_agg) +def compile_array_agg(element, compiler, **kw): + if element.order_by is not None: + return "ARRAY_AGG({0} ORDER BY {1})".format(compiler.process(element.expr), compiler.process(element.order_by)) + return "ARRAY_AGG({0})".format(compiler.process(element.expr)) + +class string_agg(ColumnElement): + type = Text() + def __init__(self, column, seperator, order_by=None): + self.column = ClauseList(*to_list(column)) + self.seperator = literal(seperator) + self.order_by = None + if order_by is not None: + self.order_by = ClauseList(*to_list(order_by)) + +@compiles(string_agg) +def compile_string_agg(element, compiler, **kw): + if element.order_by is not None: + return "STRING_AGG({0}, {1} ORDER BY {2})".format(compiler.process(element.column), compiler.process(element.seperator), compiler.process(element.order_by)) + return "STRING_AGG({0}, {1})".format(compiler.process(element.column), compiler.process(element.seperator))