table.create(..., replace=True)

[simonw]

Found myself using this pattern to quickly prototype a schema:

import sqlite_utils
db = sqlite_utils.Database(memory=True)

print(db["answers_chunks"].create({
    "id": int,
    "content": str,
    "embedding_type_id": int,
    "embedding": bytes,
    "embedding_content_md5": str,
    "source": str,
}, pk="id", transform=True).schema)

Using replace=True to drop and then recreate the table would be neat here, and would be consistent with other places that use replace=True.

[simonw]

https://sqlite-utils.datasette.io/en/stable/cli-reference.html#create-table

sqlite-utils create-table ... --replace

That also has --ignore:

  --ignore                  If table already exists, do nothing
  --replace                 If table already exists, replace it
  --transform               If table already exists, try to transform the schema

[simonw]

Here's where those are implemented for the create-table CLI command:

sqlite-utils/sqlite_utils/cli.py

Lines 1543 to 1564 in f7af238

	# Does table already exist?
	if table in db.table_names():
	if ignore:
	return
	elif replace:
	db[table].drop()
	elif transform:
	pass
	else:
	raise click.ClickException(
	'Table "{}" already exists. Use --replace to delete and replace it.'.format(
	table
	)
	)
	db[table].create(
	coltypes,
	pk=pk,
	not_null=not_null,
	defaults=dict(default),
	foreign_keys=fk,
	transform=transform,
	)

[simonw]

I think this is replace=True and ignore=True to match the CLI. And refactoring the CLI to use them.

[simonw]

Demo:

>>> from sqlite_utils import Database
>>> db = Database(memory=True)
>>> db["foo"].create({"id": int})
<Table foo (id)>
>>> db["foo"].create({"id": int})
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/simon/Dropbox/Development/sqlite-utils/sqlite_utils/db.py", line 1647, in create
    self.db.create_table(
  File "/Users/simon/Dropbox/Development/sqlite-utils/sqlite_utils/db.py", line 1030, in create_table
    self.execute(sql)
  File "/Users/simon/Dropbox/Development/sqlite-utils/sqlite_utils/db.py", line 510, in execute
    return self.conn.execute(sql)
           ^^^^^^^^^^^^^^^^^^^^^^
sqlean.dbapi2.OperationalError: table [foo] already exists
>>> db["foo"].create({"id": int}, ignore=True)
<Table foo (id)>
>>> db["foo"].create({"id": int, "name": str}, replace=True)
<Table foo (id, name)>
>>> db["foo"].create({"id": int, "name": str, "age": int}, transform=True)
<Table foo (id, name, age)>

[simonw]

Manual testing of CLI command as well:

$ sqlite-utils create-table /tmp/f.db foo id integer                         
$ sqlite-utils create-table /tmp/f.db foo id integer
Error: Table "foo" already exists. Use --replace to delete and replace it.
$ sqlite-utils create-table /tmp/f.db foo id integer --replace
$ sqlite-utils create-table /tmp/f.db foo id                  
$ sqlite-utils schema /tmp/f.db
CREATE TABLE [foo] (
   [id] INTEGER
);
$ sqlite-utils create-table /tmp/f.db foo id integer name str --transform
Error: column types must be one of ('INTEGER', 'TEXT', 'FLOAT', 'BLOB')
$ sqlite-utils create-table /tmp/f.db foo id integer name text --transform
$ sqlite-utils schema /tmp/f.db                                          
CREATE TABLE "foo" (
   [id] INTEGER,
   [name] TEXT
);
$ sqlite-utils create-table /tmp/f.db foo id integer name text --ignore   
$ sqlite-utils create-table /tmp/f.db foo id integer name text --replace
$ sqlite-utils schema /tmp/f.db                                        
CREATE TABLE [foo] (
   [id] INTEGER,
   [name] TEXT
);                                                                    

[simonw]

I think this broke a test:

$ pytest tests/test_tracer.py                           
=============================================== test session starts ================================================
platform darwin -- Python 3.11.4, pytest-7.2.2, pluggy-1.0.0
rootdir: /Users/simon/Dropbox/Development/sqlite-utils
plugins: icdiff-0.6, hypothesis-6.68.2
collected 2 items                                                                                                  

tests/test_tracer.py F.                                                                                      [100%]

===================================================== FAILURES =====================================================
___________________________________________________ test_tracer ____________________________________________________

    def test_tracer():
        collected = []
        db = Database(
            memory=True, tracer=lambda sql, params: collected.append((sql, params))
        )
        db["dogs"].insert({"name": "Cleopaws"})
        db["dogs"].enable_fts(["name"])
        db["dogs"].search("Cleopaws")
>       assert collected == [
            ("PRAGMA recursive_triggers=on;", None),
            ("select name from sqlite_master where type = 'view'", None),
            ("select name from sqlite_master where type = 'table'", None),
            ("select name from sqlite_master where type = 'view'", None),
            ("CREATE TABLE [dogs] (\n   [name] TEXT\n);\n        ", None),
            ("select name from sqlite_master where type = 'view'", None),
            ("INSERT INTO [dogs] ([name]) VALUES (?);", ["Cleopaws"]),
            ("select name from sqlite_master where type = 'view'", None),
            (
                "CREATE VIRTUAL TABLE [dogs_fts] USING FTS5 (\n    [name],\n    content=[dogs]\n)",
                None,
            ),
            (
                "INSERT INTO [dogs_fts] (rowid, [name])\n    SELECT rowid, [name] FROM [dogs];",
                None,
            ),
            ("select name from sqlite_master where type = 'view'", None),
        ]
E       assert equals failed
E         [                                                  [                                                 
E           ('PRAGMA recursive_triggers=on;', None),           ('PRAGMA recursive_triggers=on;', None),        
E           (                                                                                                  
E             "select name from sqlite_master where type =                                                     
E         'view'",                                                                                             
E             None,                                                       ...
E         
E         ...Full output truncated (13 lines hidden), use '-vv' to show

tests/test_tracer.py:12: AssertionError
============================================= short test summary info ==============================================
FAILED tests/test_tracer.py::test_tracer - assert equals failed
=========================================== 1 failed, 1 passed in 0.05s ============================================

[simonw]

Here's why that test broke:

sqlite-utils/sqlite_utils/db.py

Lines 960 to 964 in 58b5772

	if self[name].exists():
	if ignore:
	return self[name]
	elif replace:
	self[name].drop()

I added an extra if self[name].exists() check to the db.create_table() method.