⭐ Improve parameterized query support - fixes #793 (#794)

* Add parameterized query support

* Revert base Parameter constructor back to it's original signature

* Fix a few typehints and make code more DRY

* add test for PyformatParameter

* fix linting issues

---------

Co-authored-by: Lars Schwegmann <[email protected]>

Author: mvanderlee

pypika/terms.py

@@ -3,7 +3,21 @@
 import uuid
 from datetime import date
 from enum import Enum
-from typing import TYPE_CHECKING, Any, Iterable, Iterator, List, Optional, Sequence, Set, Type, TypeVar, Union
+from typing import (
+    TYPE_CHECKING,
+    Any,
+    Callable,
+    Iterable,
+    Iterator,
+    List,
+    Optional,
+    Sequence,
+    Set,
+    Tuple,
+    Type,
+    TypeVar,
+    Union,
+)
 
 from pypika.enums import Arithmetic, Boolean, Comparator, Dialects, Equality, JSONOperators, Matching, Order
 from pypika.utils import (
@@ -288,57 +302,111 @@ def get_sql(self, **kwargs: Any) -> str:
         raise NotImplementedError()
 
 
+def idx_placeholder_gen(idx: int) -> str:
+    return str(idx + 1)
+
+
+def named_placeholder_gen(idx: int) -> str:
+    return f'param{idx + 1}'
+
+
 class Parameter(Term):
     is_aggregate = None
 
     def __init__(self, placeholder: Union[str, int]) -> None:
         super().__init__()
-        self.placeholder = placeholder
+        self._placeholder = placeholder
+
+    @property
+    def placeholder(self):
+        return self._placeholder
 
     def get_sql(self, **kwargs: Any) -> str:
         return str(self.placeholder)
 
+    def update_parameters(self, param_key: Any, param_value: Any, **kwargs):
+        pass
 
-class QmarkParameter(Parameter):
-    """Question mark style, e.g. ...WHERE name=?"""
+    def get_param_key(self, placeholder: Any, **kwargs):
+        return placeholder
 
-    def __init__(self) -> None:
-        pass
 
-    def get_sql(self, **kwargs: Any) -> str:
-        return "?"
+class ListParameter(Parameter):
+    def __init__(self, placeholder: Union[str, int, Callable[[int], str]] = idx_placeholder_gen) -> None:
+        super().__init__(placeholder=placeholder)
+        self._parameters = list()
 
+    @property
+    def placeholder(self) -> str:
+        if callable(self._placeholder):
+            return self._placeholder(len(self._parameters))
 
-class NumericParameter(Parameter):
-    """Numeric, positional style, e.g. ...WHERE name=:1"""
+        return str(self._placeholder)
 
-    def get_sql(self, **kwargs: Any) -> str:
-        return ":{placeholder}".format(placeholder=self.placeholder)
+    def get_parameters(self, **kwargs):
+        return self._parameters
 
+    def update_parameters(self, value: Any, **kwargs):
+        self._parameters.append(value)
 
-class NamedParameter(Parameter):
-    """Named style, e.g. ...WHERE name=:name"""
+
+class DictParameter(Parameter):
+    def __init__(self, placeholder: Union[str, int, Callable[[int], str]] = named_placeholder_gen) -> None:
+        super().__init__(placeholder=placeholder)
+        self._parameters = dict()
+
+    @property
+    def placeholder(self) -> str:
+        if callable(self._placeholder):
+            return self._placeholder(len(self._parameters))
+
+        return str(self._placeholder)
+
+    def get_parameters(self, **kwargs):
+        return self._parameters
+
+    def get_param_key(self, placeholder: Any, **kwargs):
+        return placeholder[1:]
+
+    def update_parameters(self, param_key: Any, value: Any, **kwargs):
+        self._parameters[param_key] = value
+
+
+class QmarkParameter(ListParameter):
+    def get_sql(self, **kwargs):
+        return '?'
+
+
+class NumericParameter(ListParameter):
+    """Numeric, positional style, e.g. ...WHERE name=:1"""
 
     def get_sql(self, **kwargs: Any) -> str:
         return ":{placeholder}".format(placeholder=self.placeholder)
 
 
-class FormatParameter(Parameter):
+class FormatParameter(ListParameter):
     """ANSI C printf format codes, e.g. ...WHERE name=%s"""
 
-    def __init__(self) -> None:
-        pass
-
     def get_sql(self, **kwargs: Any) -> str:
         return "%s"
 
 
-class PyformatParameter(Parameter):
+class NamedParameter(DictParameter):
+    """Named style, e.g. ...WHERE name=:name"""
+
+    def get_sql(self, **kwargs: Any) -> str:
+        return ":{placeholder}".format(placeholder=self.placeholder)
+
+
+class PyformatParameter(DictParameter):
     """Python extended format codes, e.g. ...WHERE name=%(name)s"""
 
     def get_sql(self, **kwargs: Any) -> str:
         return "%({placeholder})s".format(placeholder=self.placeholder)
 
+    def get_param_key(self, placeholder: Any, **kwargs):
+        return placeholder[2:-2]
+
 
 class Negative(Term):
     def __init__(self, term: Term) -> None:
@@ -385,9 +453,44 @@ def get_formatted_value(cls, value: Any, **kwargs):
             return "null"
         return str(value)
 
-    def get_sql(self, quote_char: Optional[str] = None, secondary_quote_char: str = "'", **kwargs: Any) -> str:
-        sql = self.get_value_sql(quote_char=quote_char, secondary_quote_char=secondary_quote_char, **kwargs)
-        return format_alias_sql(sql, self.alias, quote_char=quote_char, **kwargs)
+    def _get_param_data(self, parameter: Parameter, **kwargs) -> Tuple[str, str]:
+        param_sql = parameter.get_sql(**kwargs)
+        param_key = parameter.get_param_key(placeholder=param_sql)
+
+        return param_sql, param_key
+
+    def get_sql(
+        self,
+        quote_char: Optional[str] = None,
+        secondary_quote_char: str = "'",
+        parameter: Parameter = None,
+        **kwargs: Any,
+    ) -> str:
+        if parameter is None:
+            sql = self.get_value_sql(quote_char=quote_char, secondary_quote_char=secondary_quote_char, **kwargs)
+            return format_alias_sql(sql, self.alias, quote_char=quote_char, **kwargs)
+
+        # Don't stringify numbers when using a parameter
+        if isinstance(self.value, (int, float)):
+            value_sql = self.value
+        else:
+            value_sql = self.get_value_sql(quote_char=quote_char, **kwargs)
+        param_sql, param_key = self._get_param_data(parameter, **kwargs)
+        parameter.update_parameters(param_key=param_key, value=value_sql, **kwargs)
+
+        return format_alias_sql(param_sql, self.alias, quote_char=quote_char, **kwargs)
+
+
+class ParameterValueWrapper(ValueWrapper):
+    def __init__(self, parameter: Parameter, value: Any, alias: Optional[str] = None) -> None:
+        super().__init__(value, alias)
+        self._parameter = parameter
+
+    def _get_param_data(self, parameter: Parameter, **kwargs) -> Tuple[str, str]:
+        param_sql = self._parameter.get_sql(**kwargs)
+        param_key = self._parameter.get_param_key(placeholder=param_sql)
+
+        return param_sql, param_key
 
 
 class JSON(Term):
@@ -551,6 +654,7 @@ def __init__(
         if isinstance(table, str):
             # avoid circular import at load time
             from pypika.queries import Table
+
             table = Table(table)
         self.table = table
 

pypika/tests/test_parameter.py

@@ -1,4 +1,5 @@
 import unittest
+from datetime import date
 
 from pypika import (
     FormatParameter,
@@ -10,6 +11,7 @@
     Query,
     Tables,
 )
+from pypika.terms import ListParameter, ParameterValueWrapper
 
 
 class ParametrizedTests(unittest.TestCase):
@@ -92,3 +94,113 @@ def test_format_parameter(self):
 
     def test_pyformat_parameter(self):
         self.assertEqual('%(buz)s', PyformatParameter('buz').get_sql())
+
+
+class ParametrizedTestsWithValues(unittest.TestCase):
+    table_abc, table_efg = Tables("abc", "efg")
+
+    def test_param_insert(self):
+        q = Query.into(self.table_abc).columns("a", "b", "c").insert(1, 2.2, 'foo')
+
+        parameter = QmarkParameter()
+        sql = q.get_sql(parameter=parameter)
+        self.assertEqual('INSERT INTO "abc" ("a","b","c") VALUES (?,?,?)', sql)
+        self.assertEqual([1, 2.2, 'foo'], parameter.get_parameters())
+
+    def test_param_select_join(self):
+        q = (
+            Query.from_(self.table_abc)
+            .select("*")
+            .where(self.table_abc.category == 'foobar')
+            .join(self.table_efg)
+            .on(self.table_abc.id == self.table_efg.abc_id)
+            .where(self.table_efg.date >= date(2024, 2, 22))
+            .limit(10)
+        )
+
+        parameter = FormatParameter()
+        sql = q.get_sql(parameter=parameter)
+        self.assertEqual(
+            'SELECT * FROM "abc" JOIN "efg" ON "abc"."id"="efg"."abc_id" WHERE "abc"."category"=%s AND "efg"."date">=%s LIMIT 10',
+            sql,
+        )
+        self.assertEqual(['foobar', '2024-02-22'], parameter.get_parameters())
+
+    def test_param_select_subquery(self):
+        q = (
+            Query.from_(self.table_abc)
+            .select("*")
+            .where(self.table_abc.category == 'foobar')
+            .where(
+                self.table_abc.id.isin(
+                    Query.from_(self.table_efg)
+                    .select(self.table_efg.abc_id)
+                    .where(self.table_efg.date >= date(2024, 2, 22))
+                )
+            )
+            .limit(10)
+        )
+
+        parameter = ListParameter(placeholder=lambda idx: f'&{idx+1}')
+        sql = q.get_sql(parameter=parameter)
+        self.assertEqual(
+            'SELECT * FROM "abc" WHERE "category"=&1 AND "id" IN (SELECT "abc_id" FROM "efg" WHERE "date">=&2) LIMIT 10',
+            sql,
+        )
+        self.assertEqual(['foobar', '2024-02-22'], parameter.get_parameters())
+
+    def test_join(self):
+        subquery = (
+            Query.from_(self.table_efg)
+            .select(self.table_efg.fiz, self.table_efg.buz)
+            .where(self.table_efg.buz == 'buz')
+        )
+
+        q = (
+            Query.from_(self.table_abc)
+            .join(subquery)
+            .on(self.table_abc.bar == subquery.buz)
+            .select(self.table_abc.foo, subquery.fiz)
+            .where(self.table_abc.bar == 'bar')
+        )
+
+        parameter = NamedParameter()
+        sql = q.get_sql(parameter=parameter)
+        self.assertEqual(
+            'SELECT "abc"."foo","sq0"."fiz" FROM "abc" JOIN (SELECT "fiz","buz" FROM "efg" WHERE "buz"=:param1)'
+            ' "sq0" ON "abc"."bar"="sq0"."buz" WHERE "abc"."bar"=:param2',
+            sql,
+        )
+        self.assertEqual({'param1': 'buz', 'param2': 'bar'}, parameter.get_parameters())
+
+    def test_join_with_parameter_value_wrapper(self):
+        subquery = (
+            Query.from_(self.table_efg)
+            .select(self.table_efg.fiz, self.table_efg.buz)
+            .where(self.table_efg.buz == ParameterValueWrapper(Parameter(':buz'), 'buz'))
+        )
+
+        q = (
+            Query.from_(self.table_abc)
+            .join(subquery)
+            .on(self.table_abc.bar == subquery.buz)
+            .select(self.table_abc.foo, subquery.fiz)
+            .where(self.table_abc.bar == ParameterValueWrapper(NamedParameter('bar'), 'bar'))
+        )
+
+        parameter = NamedParameter()
+        sql = q.get_sql(parameter=parameter)
+        self.assertEqual(
+            'SELECT "abc"."foo","sq0"."fiz" FROM "abc" JOIN (SELECT "fiz","buz" FROM "efg" WHERE "buz"=:buz)'
+            ' "sq0" ON "abc"."bar"="sq0"."buz" WHERE "abc"."bar"=:bar',
+            sql,
+        )
+        self.assertEqual({':buz': 'buz', 'bar': 'bar'}, parameter.get_parameters())
+
+    def test_pyformat_parameter(self):
+        q = Query.into(self.table_abc).columns("a", "b", "c").insert(1, 2.2, 'foo')
+
+        parameter = PyformatParameter()
+        sql = q.get_sql(parameter=parameter)
+        self.assertEqual('INSERT INTO "abc" ("a","b","c") VALUES (%(param1)s,%(param2)s,%(param3)s)', sql)
+        self.assertEqual({"param1": 1, "param2": 2.2, "param3": "foo"}, parameter.get_parameters())

pypika/tests/test_terms.py

@@ -20,7 +20,7 @@ def test_init_with_str_table(self):
         test_table_name = "test_table"
         field = Field(name="name", table=test_table_name)
         self.assertEqual(field.table, Table(name=test_table_name))
-    
+
 
 class FieldHashingTests(TestCase):
     def test_tabled_eq_fields_equally_hashed(self):