frappe-syntax-query-builder

name	frappe-syntax-query-builder
description	Use when building database queries with frappe.qb in Frappe v14-v16. Covers the PyPika-based query builder: SELECT, INSERT, UPDATE, DELETE, joins, aggregation, subqueries, cross-DB compatibility (MariaDB/PostgreSQL), and migration from raw SQL. Prevents SQL injection and DB-specific bugs. Keywords: frappe.qb, query builder, DocType, Field, pypika, join,, frappe.qb example, how to write query, join tables, SQL replacement, parameterized query. aggregate, ImportMapper, cross-database, parameterized query.
license	MIT
compatibility	Claude Code, Claude.ai Projects, Claude API. Frappe v14-v16.
metadata	{"author":"OpenAEC-Foundation","version":"3.0"}

Frappe Query Builder (frappe.qb)

Quick Reference

from frappe.query_builder import DocType, Field
from frappe.query_builder.functions import Count, Sum, IfNull
from frappe.query_builder.custom import ConstantColumn, GROUP_CONCAT
from frappe.query_builder.terms import SubQuery
from frappe.query_builder.utils import ImportMapper, db_type_is
from pypika.terms import Case, ValueWrapper
from pypika import CustomFunction, Order

Action	Pattern
SELECT	frappe.qb.from_("DocType").select("field1", "field2")
WHERE	.where(Field("status") == "Open")
ORDER	.orderby("creation", order=Order.desc)
LIMIT	.limit(10).offset(0)
JOIN	.left_join(dt2).on(dt2.name == dt1.parent)
COUNT	.select(Count("*"))
INSERT	frappe.qb.into("DocType").columns("f1", "f2").insert("v1", "v2")
UPDATE	frappe.qb.update("DocType").set("field", "value").where(...)
DELETE	frappe.qb.from_("DocType").delete().where(...)
RUN	.run() (tuples) / .run(as_dict=True) (dicts)

---

Decision Tree

Need to query the database?
│
├─ Simple get/list → frappe.db.get_value(), frappe.get_all()
│  (See frappe-core-database skill)
│
├─ Complex query with joins/aggregates/subqueries → frappe.qb ✓
│
├─ Very complex SQL not expressible in qb → frappe.db.sql()
│  (ALWAYS use parameterized values: frappe.db.sql(query, values))
│
└─ Need cross-DB compatibility → frappe.qb + ImportMapper ✓

Using frappe.qb?
│
├─ Table reference → DocType("Sales Order") — NEVER use Table()
├─ Field reference → dt.field_name or Field("field_name")
├─ Execute → .run() for tuples, .run(as_dict=True) for dicts
├─ DB-specific function → ImportMapper({db_type_is.MARIADB: X, db_type_is.POSTGRES: Y})
└─ Get SQL string → query.get_sql() — NEVER pass to frappe.db.sql()

---

Core Patterns

SELECT with DocType

# ALWAYS use DocType() for table references — adds "tab" prefix
so = frappe.qb.DocType("Sales Order")
soi = frappe.qb.DocType("Sales Order Item")

orders = (
    frappe.qb.from_(so)
    .select(so.name, so.customer, so.grand_total)
    .where(so.status == "To Deliver and Bill")
    .where(so.docstatus == 1)
    .orderby(so.creation, order=Order.desc)
    .limit(20)
    .run(as_dict=True)
)

JOIN

result = (
    frappe.qb.from_(so)
    .left_join(soi).on(soi.parent == so.name)
    .select(so.name, so.customer, soi.item_code, soi.qty)
    .where(so.docstatus == 1)
    .where(soi.item_code.like("ITEM-%"))
    .run(as_dict=True)
)

Aggregation

from frappe.query_builder.functions import Count, Sum

gl = frappe.qb.DocType("GL Entry")
result = (
    frappe.qb.from_(gl)
    .select(gl.account, Sum(gl.debit).as_("total_debit"), Count("*").as_("entries"))
    .where(gl.docstatus == 1)
    .groupby(gl.account)
    .run(as_dict=True)
)

# Shortcut aggregation methods
total = frappe.qb.sum("GL Entry", "debit", filters={"account": "Sales"})
max_qty = frappe.qb.max("Stock Ledger Entry", "actual_qty", filters={"item_code": "ITEM-001"})

INSERT / UPDATE / DELETE

# INSERT
frappe.qb.into("Activity Log").columns("user", "action").insert("admin", "login").run()

# UPDATE
customer = frappe.qb.DocType("Customer")
(frappe.qb.update(customer)
    .set(customer.status, "Active")
    .where(customer.name == "CUST-001")
    .run())

# DELETE
frappe.qb.from_("Error Log").delete().where(Field("creation") < "2024-01-01").run()

---

Filtering

dt = frappe.qb.DocType("Sales Order")

# Equality
.where(dt.status == "Open")

# OR (pipe operator)
.where((dt.status == "Open") | (dt.status == "Draft"))

# AND (chain .where() calls)
.where(dt.status == "Open")
.where(dt.docstatus == 1)

# LIKE
.where(dt.customer.like("CUST-%"))

# IN
.where(dt.status.isin(["Open", "Draft"]))

# BETWEEN (bracket syntax)
.where(dt.creation[start_date:end_date])

# NULL checks
.where(dt.email.isnotnull())
.where(dt.phone.isnull())

# Comparison
.where(dt.grand_total > 1000)
.where(dt.grand_total >= 500)
.where(dt.status != "Cancelled")

---

Cross-DB Compatibility

from frappe.query_builder.utils import ImportMapper, db_type_is
from frappe.query_builder.custom import GROUP_CONCAT, STRING_AGG

# ImportMapper selects correct function per database
GroupConcat = ImportMapper({
    db_type_is.MARIADB: GROUP_CONCAT,
    db_type_is.POSTGRES: STRING_AGG,
})

dt = frappe.qb.DocType("Has Role")
result = (
    frappe.qb.from_(dt)
    .select(dt.parent, GroupConcat(dt.role))
    .groupby(dt.parent)
    .run(as_dict=True)
)

MariaDB	PostgreSQL	Use ImportMapper
GROUP_CONCAT	STRING_AGG	Yes
MATCH...AGAINST	TO_TSVECTOR	Yes
Locate	Strpos	Yes
Timestamp	Extract-based	Auto-handled

---

Anti-patterns

1. NEVER pass qb query to frappe.db.sql() — bypasses parameterization
2. NEVER use Table() for DocTypes — use DocType() (adds tab prefix)
3. NEVER forget .run() — without it you get a query object, not results
4. NEVER use raw SQL strings in frappe.get_all(fields=[...]) — use dict syntax
5. ALWAYS use ImportMapper for DB-specific functions
6. ALWAYS chain .run(as_dict=True) when you need dicts — default is tuples

---

Version Differences

Feature	v14	v15	v16
Core qb API	Introduced	Yes	Yes
ImportMapper	Yes	Yes	Yes
SQLite backend	--	--	Added
Masked fields	--	--	Added
Union queries (.walk)	--	Added	Yes
Child query execution	--	--	Added

---

Reference Files

• Functions & Aggregates — All available qb functions
• Migration Guide — Converting raw SQL and get_all patterns
• Cross-DB Patterns — ImportMapper and DB-specific functions