Построение Raw-SQL cредствами Storm-ORM¶
Возникло у меня желание попробовать построить чистый, сырой запрос (Raw-SQL) с помощью storm.expr для одного самописного специфического маппера, сочетающего в себе паттерны Single Table Inheritance и Entity Attribute Value.
Причем, параметризирование запроса должно выполняться именованными (а не позиционными) аргументами, без участия Storm ORM.
И вот что у меня получилось (конкретная реализация, структура и названия, естественно, изменены):
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 | import sqlparse
from storm.expr import (
Add, Alias, build_tables, Column, COLUMN, Comparable, Count, EXPR, has_tables, In, LeftJoin,
NamedFunc, Select, SQL, SQLRaw, Sum, Table as TableOrig, TABLE, Undef
)
from storm.databases.mysql import compile as compile
from storm.variables import Variable
compile = compile.create_child()
@compile.when(int, long)
def compile_int(compile, expr, state):
return str(expr)
@compile.when(Variable)
def compile_variable(compile, variable, state):
value = variable.get(to_db=True)
if isinstance(value, (int, long)):
return str(value)
state.parameters.append(variable)
return "?"
@compile.when(Select)
def compile_select(compile, select, state):
tokens = ["SELECT "]
state.push("auto_tables", [])
state.push("context", COLUMN)
if select.distinct:
tokens.append("DISTINCT ")
if isinstance(select.distinct, (tuple, list)):
tokens.append(
"ON (%s) " % compile(select.distinct, state, raw=True))
tokens.append(compile(select.columns, state))
tables_pos = len(tokens)
parameters_pos = len(state.parameters)
state.context = EXPR
if select.where is not Undef:
tokens.append(" WHERE ")
tokens.append(compile(select.where, state, raw=True))
if select.group_by is not Undef:
tokens.append(" GROUP BY ")
tokens.append(compile(select.group_by, state, raw=True))
if select.having is not Undef:
tokens.append(" HAVING ")
tokens.append(compile(select.having, state, raw=True))
if select.order_by is not Undef:
tokens.append(" ORDER BY ")
tokens.append(compile(select.order_by, state, raw=True))
if select.limit is not Undef: # patched
tokens.append(" LIMIT ")
tokens.append(compile(select.limit, state, raw=True))
if select.offset is not Undef: # patched
tokens.append(" OFFSET ")
tokens.append(compile(select.offset, state, raw=True))
if has_tables(state, select):
state.context = TABLE
state.push("parameters", [])
tokens.insert(tables_pos, " FROM ")
tokens.insert(tables_pos+1, build_tables(compile, select.tables,
select.default_tables, state))
parameters = state.parameters
state.pop()
state.parameters[parameters_pos:parameters_pos] = parameters
state.pop()
state.pop()
return "".join(tokens)
S = SQL
def as_(self, name=Undef):
return Alias(self, name)
Comparable.as_ = as_
class If(NamedFunc):
__slots__ = ()
name = "IF"
class Space(object):
def __init__(self, factory):
self._factory = factory
def __getattr__(self, name):
return self._factory(name)
C = Space(Column)
class Param(SQL):
__slots__ = ()
def __init__(self, expr):
expr = '%({})s'.format(expr)
SQL.__init__(self, expr)
P = Space(Param)
class Table(TableOrig):
__slots__ = ()
def __getattr__(cls, name):
return Column(name, cls)
def as_(cls, name=Undef):
return TableAlias(cls, name)
T = Space(Table)
class TableAlias(Alias):
def __getattr__(cls, name):
return Column(name, cls)
# ============================================
# Ok,preparations is done, now let build query
# ============================================
class EventMapper(object):
_compile = compile
class BaseQuery(object):
def __init__(self):
meta_ta = T.stats_posts_meta.as_('i')
self.event_where = []
self.event_having = Add()
self.event_query = self._create_event_query(self.event_where, self.event_having)
self.info_query = self._create_info_query(TableAlias(self.event_query, 'e'), meta_ta)
self.final_query = self._create_final_query(TableAlias(self.info_query, 'e'))
def _create_event_query(self, where, having):
event_ta = Table('entity_events_daily').as_('e')
return Select(
columns=[
Alias(None, 'TIMESTAMP'),
Alias(None, 'user_id'),
event_ta.entity_id.as_('entity_id'),
],
tables=event_ta,
where=(
(event_ta.site_id == P.site_id) &
(event_ta.category_id == P.category_id) &
(event_ta.timestamp >= P.min_timestamp) &
(event_ta.timestamp < P.max_timestamp) &
In(event_ta.event_id, where)
),
group_by=[event_ta.entity_id],
having=(
(C.created_entity_count >= P.min_entity_creation_count) &
(having > 0)
)
)
def _create_info_query(self, event_query_ta, meta_ta):
return Select(
columns=[
Alias(None, 'entity_id'),
Alias(None, 'TIMESTAMP'),
Count().as_('active_entity_count'),
meta_ta.owner_id.as_('owner_id'),
],
tables=LeftJoin(
event_query_ta,
meta_ta,
on=(meta_ta.entity_id == event_query_ta.entity_id)),
group_by=[meta_ta.owner_id]
)
def _create_final_query(self, info_ta):
return Select(
columns=[SQLRaw('*')],
tables=info_ta,
offset=P.offset,
limit=P.limit
)
def add_criteria(self, *names):
for name in names:
self.add_criterion(name)
def add_criterion(self, name):
count_name = "{}_count".format(name)
self.event_query.columns.append(
Sum(If(C.event_id.is_in(Param(name)), C.event_count, 0)).as_(count_name),
)
self.event_where.append(Param(name))
self.event_having.exprs += (Column(count_name),)
self.info_query.columns.append(
Sum(Column(count_name)).as_(count_name)
)
def get(self):
return self.final_query
def find_by_criteria(self, **criteria):
query = self.BaseQuery()
query.add_criteria(*criteria.keys())
return self._execute(query, criteria.values())
def _execute(self, query, params=()):
print sqlparse.format(self._compile(query.get()), reindent=True, keyword_case='upper')
event_mapper = EventMapper()
object_list = event_mapper.find_by_criteria(
comments=1,
internal_shares=2,
external_shares=3,
internal_likes=4,
external_likes=5,
entity_creations=6,
views=7,
clicks=8
)
|
На выходе получается запрос вида:
SELECT *
FROM
(SELECT NULL AS entity_id,
NULL AS `TIMESTAMP`,
COUNT(*) AS active_entity_count,
i.owner_id AS owner_id,
SUM(entity_creations_count) AS entity_creations_count,
SUM(views_count) AS views_count,
SUM(internal_shares_count) AS internal_shares_count,
SUM(comments_count) AS comments_count,
SUM(external_shares_count) AS external_shares_count,
SUM(external_likes_count) AS external_likes_count,
SUM(internal_likes_count) AS internal_likes_count,
SUM(clicks_count) AS clicks_count
FROM
(SELECT NULL AS `TIMESTAMP`,
NULL AS user_id,
e.entity_id AS entity_id,
SUM(IF((event_id IN (%(entity_creations)s)), event_count, 0)) AS entity_creations_count,
SUM(IF((event_id IN (%(views)s)), event_count, 0)) AS views_count,
SUM(IF((event_id IN (%(internal_shares)s)), event_count, 0)) AS internal_shares_count,
SUM(IF((event_id IN (%(comments)s)), event_count, 0)) AS comments_count,
SUM(IF((event_id IN (%(external_shares)s)), event_count, 0)) AS external_shares_count,
SUM(IF((event_id IN (%(external_likes)s)), event_count, 0)) AS external_likes_count,
SUM(IF((event_id IN (%(internal_likes)s)), event_count, 0)) AS internal_likes_count,
SUM(IF((event_id IN (%(clicks)s)), event_count, 0)) AS clicks_count
FROM entity_events_daily AS e
WHERE e.site_id = %(site_id)s
AND e.category_id = %(category_id)s
AND e.`timestamp` >= %(min_timestamp)s
AND e.`timestamp` < %(max_timestamp)s
AND e.event_id IN (%(entity_creations)s,
%(views)s,
%(internal_shares)s,
%(comments)s,
%(external_shares)s,
%(external_likes)s,
%(internal_likes)s,
%(clicks)s)
GROUP BY e.entity_id
HAVING created_entity_count >= %(min_entity_creation_count)s
AND entity_creations_count+views_count+internal_shares_count+comments_count+external_shares_count+external_likes_count+internal_likes_count+clicks_count > 0) AS e
LEFT JOIN stats_posts_meta AS i ON i.entity_id = e.entity_id
GROUP BY i.owner_id) AS e LIMIT %(limit)s
OFFSET %(offset)s
