From 2f7c78b266a09e27beaf418b42f47249a7e46170 Mon Sep 17 00:00:00 2001
From: saxenabhishek <as7122000@gmail.com>
Date: Thu, 15 Jul 2021 02:00:50 +0530
Subject: [PATCH] refactor: qb in patch v12 set_correct_assign_value_in_docs

---
 .../v12_0/set_correct_assign_value_in_docs.py | 32 +++++++++----------
 frappe/query_builder/custom_functions.py      | 12 +++++++
 frappe/query_builder/qb.py                    | 21 ++++++++----
 3 files changed, 42 insertions(+), 23 deletions(-)
 create mode 100644 frappe/query_builder/custom_functions.py

diff --git a/frappe/patches/v12_0/set_correct_assign_value_in_docs.py b/frappe/patches/v12_0/set_correct_assign_value_in_docs.py
index 65a635c170..72e71c8314 100644
--- a/frappe/patches/v12_0/set_correct_assign_value_in_docs.py
+++ b/frappe/patches/v12_0/set_correct_assign_value_in_docs.py
@@ -1,25 +1,23 @@
 import frappe
 
+
 def execute():
-	frappe.reload_doc('desk', 'doctype', 'todo')
+	frappe.reload_doc("desk", "doctype", "todo")
 
-	query = '''
-		SELECT
-			name, reference_type, reference_name, {} as assignees
-		FROM
-			`tabToDo`
-		WHERE
-			COALESCE(reference_type, '') != '' AND
-			COALESCE(reference_name, '') != '' AND
-			status != 'Cancelled'
-		GROUP BY
-			reference_type, reference_name
-	'''
+	ToDo = frappe.qb.Table("ToDo")
+	assignees = frappe.qb.GROUP_CONCAT("owner").distinct().as_("assignees")
 
-	assignments = frappe.db.multisql({
-		'mariadb': query.format('GROUP_CONCAT(DISTINCT `owner`)'),
-		'postgres': query.format('STRING_AGG(DISTINCT "owner", ",")')
-	}, as_dict=True)
+	q = (
+		frappe.qb.from_(ToDo)
+		.select(ToDo.name, ToDo.reference_type, assignees)
+		.where(frappe.qb.fn.Coalesce(ToDo.reference_type, "") != "")
+		.where(frappe.qb.fn.Coalesce(ToDo.reference_name, "") != "")
+		.where(ToDo.status != "Cancelled")
+		.groupby(ToDo.reference_type, ToDo.reference_name)
+		.get_sql()
+	)
+
+	assignments = frappe.db.sql(q, as_dict=True)
 
 	for doc in assignments:
 		assignments = doc.assignees.split(',')
diff --git a/frappe/query_builder/custom_functions.py b/frappe/query_builder/custom_functions.py
new file mode 100644
index 0000000000..446a4df2d2
--- /dev/null
+++ b/frappe/query_builder/custom_functions.py
@@ -0,0 +1,12 @@
+from pypika import functions as fn
+
+
+
+class GROUP_CONCAT(fn.DistinctOptionFunction):
+    def __init__(self, col, alias=None):
+        super(GROUP_CONCAT, self).__init__("GROUP_CONCAT", col, alias=alias)
+
+
+class STRING_AGG(fn.DistinctOptionFunction):
+    def __init__(self, col, val=",", alias=None):
+        super(STRING_AGG, self).__init__("STRING_AGG", col, val, alias=alias)
diff --git a/frappe/query_builder/qb.py b/frappe/query_builder/qb.py
index ddf514ab2c..fb92eed56b 100644
--- a/frappe/query_builder/qb.py
+++ b/frappe/query_builder/qb.py
@@ -2,6 +2,7 @@ from pypika import MySQLQuery, Order, PostgreSQLQuery
 from pypika import functions as fn
 from pypika import terms
 from pypika.queries import Schema, Table
+from .custom_functions import GROUP_CONCAT, STRING_AGG
 
 def qb(db_type):
 	if not db_type:
@@ -14,19 +15,25 @@ class common:
 	terms = terms
 	desc = Order.desc
 	Schema = Schema
+	@staticmethod
+	def Table(classname:str, *args, **kwargs):
+		if not classname.startswith("__"):
+			classname = "tab" + classname
+		return Table(classname, *args, **kwargs)
 
-class MariaDB(MySQLQuery,common):
+class MariaDB(common, MySQLQuery,):
 	Field = terms.Field
+	GROUP_CONCAT = GROUP_CONCAT
 
 	def __init__(self) -> None:
 		super().__init__()
-	
+
 	@classmethod
 	def from_(cls, class_name, *args, **kwargs):
 		if isinstance(class_name,str):
 			class_name = "tab"+class_name
 		return super().from_(class_name, *args, **kwargs)
-	
+
 	@staticmethod
 	def rename_table(old_name, new_name):
 		return f"RENAME TABLE `tab{old_name}` TO `tab{new_name}`"
@@ -39,9 +46,11 @@ class MariaDB(MySQLQuery,common):
 	def change_table_type(tb, col, type):
 		return f"ALTER TABLE `{tb}` MODIFY `{col}` {type} NOT NULL"
 
-class Postgres(PostgreSQLQuery,common):
+
+class Postgres(common, PostgreSQLQuery,):
 	postgres_field = {"table_name": "relname", "table_rows": "n_tup_ins"}
 	information_schema_translation = {"tables": "pg_stat_all_tables"}
+	GROUP_CONCAT = STRING_AGG
 
 	def __init__(self) -> None:
 		super().__init__()
@@ -63,11 +72,11 @@ class Postgres(PostgreSQLQuery,common):
 			class_name = "tab" + class_name
 
 		return super().from_(class_name, *args, **kwargs)
-	
+
 	@staticmethod
 	def rename_table(old_name, new_name):
 		return f"ALTER TABLE `tab{old_name}` RENAME TO `tab{new_name}`"
-	
+
 	@staticmethod
 	def DESC(dt):
 		return f"SELECT COLUMN_NAME FROM information_schema.COLUMNS WHERE TABLE_NAME = 'tab{dt}'"