Database API
frappe.db.get_list
frappe.db.get_list(doctype, filters, or_filters, fields, order_by, group_by, start, page_length)
- Also aliased to
frappe.get_list
Returns a list of records from a doctype
table. ORM Wrapper for a SELECT
query. Will also apply user permissions for the records for the session user. Only returns the document names if the fields
keyword argument is not given. By default this method returns a list of dict
s, but, you can pluck a particular field by giving the pluck
keyword argument:
frappe.db.get_list('Employee')
# output
[{'name': 'HR-EMP-00008'},
{'name': 'HR-EMP-00006'},
{'name': 'HR-EMP-00010'},
{'name': 'HR-EMP-00005'}
]
# with pluck
frappe.db.get_list('Employee', pluck='name')
# output
['HR-EMP-00008',
'HR-EMP-00006',
'HR-EMP-00010',
'HR-EMP-00005'
]
Combining filters and other arguments:
frappe.db.get_list('Task',
filters={
'status': 'Open'
},
fields=['subject', 'date'],
order_by='date desc',
start=10,
page_length=20,
as_list=True
)
# output
(('Update Branding and Design', '2019-09-04'),
('Missing Documentation', '2019-09-02'),
('Fundraiser for Foundation', '2019-09-03'))
# Tasks with date after 2019-09-08
frappe.db.get_list('Task', filters={
'date': ['>', '2019-09-08']
})
# Tasks with date between 2020-04-01 and 2021-03-31 (both inclusive)
frappe.db.get_list('Task', filters=[[
'date', 'between', ['2020-04-01', '2021-03-31']
]])
# Tasks with subject that contains "test"
frappe.db.get_list('Task', filters={
'subject': ['like', '%test%']
})
# Count number of tasks grouped by status
frappe.db.get_list('Task',
fields=['count(name) as count', 'status'],
group_by='status'
)
# output
[{'count': 1, 'status': 'Working'},
{'count': 2, 'status': 'Overdue'},
{'count': 2, 'status': 'Open'},
{'count': 1, 'status': 'Filed'},
{'count': 20, 'status': 'Completed'},
{'count': 1, 'status': 'Cancelled'}]
frappe.db.get_all
frappe.db.get_all(doctype, filters, or_filters, fields, order_by, group_by, start, page_length)
- Also aliased to
frappe.get_all
Same as frappe.db.get_list
but will fetch all records without applying permissions.
frappe.db.get_value
frappe.db.get_value(doctype, name, fieldname)
or frappe.db.get_value(doctype, filters, fieldname)
- Also aliased to
frappe.get_value
andfrappe.db.get_values
Returns a document's field value or a list of values.
# single value
subject = frappe.db.get_value('Task', 'TASK00002', 'subject')
# multiple values
subject, description = frappe.db.get_value('Task', 'TASK00002', ['subject', 'description'])
# as dict
task_dict = frappe.db.get_value('Task', 'TASK00002', ['subject', 'description'], as_dict=1)
task_dict.subject
task_dict.description
# with filters, will return the first record that matches filters
subject, description = frappe.db.get_value('Task', {'status': 'Open'}, ['subject', 'description'])
frappe.db.get_single_value
frappe.db.get_single_value(doctype, fieldname)
Returns a field value from a Single DocType.
timezone = frappe.db.get_single_value('System Settings', 'timezone')
frappe.db.set_value
frappe.db.set_value(doctype, name, fieldname, value)
- Also aliased to
frappe.db.update
Sets a field's value in the database, does not call the ORM triggers but updates the modified timestamp (unless specified not to).
# update a field value
frappe.db.set_value('Task', 'TASK00002', 'subject', 'New Subject')
# update multiple values
frappe.db.set_value('Task', 'TASK00002', {
'subject': 'New Subject',
'description': 'New Description'
})
# update without updating the `modified` timestamp
frappe.db.set_value('Task', 'TASK00002', 'subject', 'New Subject', update_modified=False)
This method won't call ORM triggers like
validate
andon_update
. Use this method to update hidden fields or if you know what you are doing.
frappe.db.exists
frappe.db.exists(doctype, name)
Returns true if a document record exists.
Pass doctype and docname:
frappe.db.exists("User", "jane@example.org", cache=True)
Pass a dict of filters including the "doctype"
key:
frappe.db.exists({"doctype": "User", "full_name": "Jane Doe"})
Pass the doctype and a dict of filters:
frappe.db.exists("User", {"full_name": "Jane Doe"})
frappe.db.count
frappe.db.count(doctype, filters)
Returns number of records for a given doctype
and filters
.
# total number of Task records
frappe.db.count('Task')
# total number of Open tasks
frappe.db.count('Task', {'status': 'Open'})
frappe.db.delete
frappe.db.delete(doctype, filters)
Delete doctype
records that match filters
. This runs a DML command, which means it can be rolled back. If no filters specified, all the records of the doctype are deleted.
frappe.db.delete("Route History", {
"modified": ("<=", last_record_to_keep[0].modified),
"user": user
})
frappe.db.delete("Error Log")
frappe.db.delete("__Test Table")
You may pass the doctype name or an internal table name. Conventionally, internal tables in Frappe are prefixed with __
. The API follows this. The above commands run an unconditional DELETE
query over tables tabError Log and __Test Table.
frappe.db.truncate
frappe.db.truncate(doctype)
Truncate a table in the database. This runs a DDL command TRUNCATE TABLE
, a commit is triggered before the statement is executed. This action cannot be rolled back. You may want to use this for clearing out log tables periodically.
frappe.db.truncate("Error Log")
frappe.db.truncate("__Test Table")
The above commands run a TRUNCATE
query over tables tabError Log and __Test Table.
frappe.db.commit
frappe.db.commit()
Commits current transaction. Calls SQL COMMIT
.
In most cases you don't need to commit manually. Refer Frappe's Database transaction model below.
frappe.db.savepoint
frappe.db.savepoint(save_point)
Create a named savepoint to which you can later roll back to.
frappe.db.rollback
frappe.db.rollback()
Rollbacks current transaction. Calls SQL ROLLBACK
.
Frappe will automatically run
frappe.db.rollback()
if an exception is thrown during a Web Request of typePOST
orPUT
. Use this if you have to rollback early in a transaction.
frappe.db.rollback(save_point="save_point_name")
Rollback to a specific savepoint instead rolling back full transactions. This rollback won't undo changes done to filesytem and any other rollback watchers.
frappe.db.sql
frappe.db.sql(query, values, as_dict)
Execute an arbitrary SQL query. This may be useful for complex server side reports with join statements, adjusting the database to new features, etc.
Example:
values = {'company': 'Frappe Technologies Inc'}
data = frappe.db.sql("""
SELECT
acc.account_number
gl.debit
gl.credit
FROM `tabGL Entry` gl
LEFT JOIN `tabAccount` acc
ON gl.account = acc.name
WHERE gl.company = %(company)s
""", values=values, as_dict=0)
Avoid using this method as it will bypass validations and integrity checks. It's always better to use frappe.get_doc, frappe.db.get_list, etc., if possible.
frappe.db.multisql
frappe.db.multisql({'mariadb': mariadb_query, 'postgres': postgres_query})
Execute the suitable SQL statement for any supported database engine.
frappe.db.rename_table
frappe.db.rename_table(old_name, new_name)
Executes a query to change table name. Specify the DocType or internal table's name directly to rename the table.
Example:
frappe.db.rename_table("__internal_cache", "__temporary_cache")
frappe.db.rename_table("todo", "ToDo")
The second example should be used only if you understand the ramifications of it.
Don't use this to rename DocType tables. Use
frappe.rename_doc
for that instead
frappe.db.describe
frappe.db.describe(doctype)
Returns a tuple of the table description for given DocType.
frappe.db.change_column_type
frappe.db.change_column_type(doctype, column, new_type)
Changes the type of column for specified DocType.
frappe.db.add_index
frappe.db.add_index(doctype, fields, index_name)
Creates indexes for doctypes for the specified fields.
Note: if you want an index on a TEXT or a BLOB field, you must specify a fixed length to do that.
Example:
frappe.db.add_index("Notes", ["id(10)", "content(500)"], index_name)
frappe.db.add_unique
frappe.db.add_unique(doctype, fields, constraint_name=None)
Creates unique constraint for doctypes for the specified fields.
Example:
frappe.db.add_unique("DoctypeName",["field1","field2"])
Database transaction hooks
Frappe provides hooks for running callbacks before/after transaction commands like commit/rollback are issued. These hooks are useful for:
- Rolling back changes that are done outside of the database if the transaction is rolled back
- Flushing changes outside of the database only if the transaction is committed.
These hooks are :
frappe.db.before_commit.add(func: Callable)
frappe.db.after_commit.add(func: Callable)
frappe.db.before_rollback.add(func: Callable)
frappe.db.after_rollback.add(func: Callable)
Example usage:
def create_file(self):
self.write_file()
# This ensures rollback if DB transaction is rolledback
frappe.db.after_rollback.add(self.rollback_file)
def rollback_file(self):
self.delete_file()
Database transaction model
Frappe's database abstractions implement a sane transaction model by default. So in most cases, you won't have to deal with SQL transactions manually. A broad description of this model is described below:
Web requests
- While performing
POST
orPUT
, if any writes were made to the database, they are committed at end of the successful request. - AJAX calls made using
frappe.call
arePOST
by default unless changed. GET
requests do not cause an implicit commit.- Any uncaught exception during handling of request will rollback the transaction.
Background/scheduled Jobs
- Calling a function as background or scheduled job will commit the transaction after successful completion.
- Any uncaught exception will cause rollback of the transaction.
Patches
- Successful completion of the patch's
execute
function will commit the transaction automatically. - Any uncaught exception will cause rollback of the transaction.
Unit tests
- Transaction is committed after running one test module. Test module means any python test file like
test_core.py
. - Transaction is also committed after finishing all tests.
- Any uncaught exception will exit the test runner, hence won't commit.
Note: If you're catching exceptions anywhere, then database abstraction does not know that something has gone wrong hence you're responsible for the correct rollback of the transaction.