perf(patch): Use INSERT with ON DUPLICATE KEY UPDATE

update_total_qty_field patch was using UPDATE statement with CASE

Now use INSERT INTO with ON DUPLICATE KEY UPDATE clause which
allows this query to use indexes and update multiple rows per query.
This commit is contained in:
Aditya Hase 2018-11-14 18:58:30 +05:30
parent e4193030b1
commit d168a71cfb

View File

@ -9,12 +9,12 @@ def execute():
frappe.reload_doc('stock', 'doctype', 'purchase_receipt')
frappe.reload_doc('accounts', 'doctype', 'sales_invoice')
frappe.reload_doc('accounts', 'doctype', 'purchase_invoice')
doctypes = ["Sales Order", "Sales Invoice", "Delivery Note",\
"Purchase Order", "Purchase Invoice", "Purchase Receipt", "Quotation", "Supplier Quotation"]
for doctype in doctypes:
total_qty = frappe.db.sql('''
total_qty = frappe.db.sql('''
SELECT
parent, SUM(qty) as qty
FROM
@ -22,14 +22,25 @@ def execute():
GROUP BY parent
''' % (doctype), as_dict = True)
when_then = []
for d in total_qty:
when_then.append("""
when dt.name = '{0}' then {1}
""".format(frappe.db.escape(d.get("parent")), d.get("qty")))
# Query to update total_qty might become too big, Update in batches
# batch_size is chosen arbitrarily, Don't try too hard to reason about it
batch_size = 100000
for i in range(0, len(total_qty), batch_size):
batch_transactions = total_qty[i:i + batch_size]
if when_then:
frappe.db.sql('''
UPDATE
`tab%s` dt SET dt.total_qty = CASE %s ELSE 0.0 END
''' % (doctype, " ".join(when_then)))
# UPDATE with CASE for some reason cannot use PRIMARY INDEX,
# causing all rows to be examined, leading to a very slow update
# UPDATE with WHERE clause uses PRIMARY INDEX, but will lead to too many queries
# INSERT with ON DUPLICATE KEY UPDATE uses PRIMARY INDEX
# and can perform multiple updates per query
# This is probably never used anywhere else as of now, but should be
values = []
for d in batch_transactions:
values.append("('{}', {})".format(d.parent, d.qty))
conditions = ",".join(values)
frappe.db.sql("""
INSERT INTO `tab{}` (name, total_qty) VALUES {}
ON DUPLICATE KEY UPDATE name = VALUES(name), total_qty = VALUES(total_qty)
""".format(doctype, conditions))