issues

I used a custom SQL function in a migration script and then realized that it should be de-registered before the end of the script to avoid leaking into the calling code.

I got this error trying to drop a column from a table that was part of a SQL view:

error in view plugins: no such table: main.pypi_releases

Upon further investigation I found that this pattern seemed to fix it: python def transform_the_table(conn): # Run this in a transaction: with conn: # We have to read all the views first, because we need to drop and recreate them db = sqlite_utils.Database(conn) views = {v.name: v.schema for v in db.views if table.lower() in v.schema.lower()} for view in views.keys(): db[view].drop() db[table].transform( types=types, rename=rename, drop=drop, column_order=[p[0] for p in order_pairs], ) # Now recreate the views for name, schema in views.items(): db.create_view(name, schema) So grab a copy of any view that might reference this table, start a transaction, drop those views, run the transform, recreate the views again.

I wonder if this should become an option in sqlite-utils? Maybe a recreate_views=True argument for table.tranform(...)? Should it be opt-in or opt-out?

Originally posted by @simonw in https://github.com/simonw/datasette-edit-schema/issues/35#issuecomment-1683370548

Added in: - #483

I don't know how to fix this in Sphinx: I'm getting this: https://sqlite-utils.datasette.io/en/latest/cli.html#cli-install

The insert –convert and query –functions options

But I want it to display insert --convert and not insert –convert there.

Here's the code: https://github.com/simonw/sqlite-utils/blob/85247038f70d7eb2f3e272cfeaa4c44459cafba8/docs/cli.rst#L2125

This can be a documented wrapper around with db.conn:.

https://sqlite-utils.datasette.io/en/stable/cli.html#csv-files-without-a-header-row

The first row of any CSV or TSV file is expected to contain the names of the columns in that file.

If your file does not include this row, you can use the --no-headers option to specify that the tool should not use that fist row as headers.

If you do this, the table will be created with column names called untitled_1 and untitled_2 and so on. You can then rename them using the sqlite-utils transform ... --rename command.

It would be nice to be able to specify the column names when importing CSV/TSV without a header row, via an extra command line option.

(renaming a column of a large table can take a long time, which makes it an inconvenient workaround)

I am building a database, in which one of the tables has a many-to-many relationship to itself. As far as I can see, this is not (yet) possible using .m2m() in sqlite-utils. This may be a bit of a niche use case, so feel free to close this issue if you feel it would introduce too much complexity compared to the benefits.

Example: suppose I have a table of people, and I want to store the information that John and Mary have two children, Michael and Suzy. It would be neat if I could do something like this:

```python from sqlite_utils import Database

db = Database(memory=True) db["people"].insert({"name": "John"}, pk="name").m2m( "people", [{"name": "Michael"}, {"name": "Suzy"}], m2m_table="parent_child", pk="name" ) db["people"].insert({"name": "Mary"}, pk="name").m2m( "people", [{"name": "Michael"}, {"name": "Suzy"}], m2m_table="parent_child", pk="name" ) ```

But if I do that, the many-to-many table parent_child has only one column: CREATE TABLE [parent_child] ( [people_id] TEXT REFERENCES [people]([name]), PRIMARY KEY ([people_id], [people_id]) )

This could be solved by adding one or two keyword_arguments to .m2m(), e.g. .m2m(..., left_name=None, right_name=None) or .m2m(..., names=(None, None)).

I'm writing code for https://github.com/simonw/git-history/issues/33 that creates a table inside a loop:

python item_pk = db[item_table].lookup( {"_item_id": item_id}, item_to_insert, column_order=("_id", "_item_id"), pk="_id", ) I need to look things up by _item_id on this table, which means I need an index on that column (the table can get very big).

But there's no mechanism in SQLite utils to detect if the table was created for the first time and add an index to it. And I don't want to run CREATE INDEX IF NOT EXISTS every time through the loop.

This should work like the foreign_keys= mechanism.

Inspired by work on git-history where I used this pattern: ```python column_name_to_id = {}

def column_id(column):
    if column not in column_name_to_id:
        id = db["columns"].lookup(
            {"namespace": namespace_id, "name": column},
            foreign_keys=(("namespace", "namespaces", "id"),),
        )
        column_name_to_id[column] = id
    return column_name_to_id[column]

`` If you're going to be doing a large number oftable.lookup(...)` calls and you know that no other script will be modifying the database at the same time you can presumably get a big speedup using a Python in-memory cache - maybe even a LRU one to avoid memory bloat.

@simonw any thoughts on allow extracts to specify the lookup column name? If I'm understanding the documentation right, .lookup() allows you to define the "value" column (the documentation uses name), but when you use extracts keyword as part of .insert(), .upsert() etc. the lookup must be done against a column named "value". I have an existing lookup table that I've populated with columns "id" and "name" as opposed to "id" and "value", and seems I can't use extracts=, unless I'm missing something...

Initial thought on how to do this would be to allow the dictionary value to be a tuple of table name column pair... so: table = db.table("trees", extracts={"species_id": ("Species", "name"})

I haven't dug too much into the existing code yet, but does this make sense? Worth doing?

Originally posted by @chrishas35 in https://github.com/simonw/sqlite-utils/issues/46#issuecomment-592999503

Originally posted by @simonw in https://github.com/simonw/sqlite-utils/pull/118#issuecomment-655283393

We should put some thought into how this library supports and encourages smart use of transactions.

It turns out SQLite supports composite foreign keys: https://www.sqlite.org/foreignkeys.html#fk_composite

Their example looks like this: ```sql CREATE TABLE album( albumartist TEXT, albumname TEXT, albumcover BINARY, PRIMARY KEY(albumartist, albumname) );

CREATE TABLE song( songid INTEGER, songartist TEXT, songalbum TEXT, songname TEXT, FOREIGN KEY(songartist, songalbum) REFERENCES album(albumartist, albumname) ); ```

Here's what that looks like in sqlite-utils:

``` In [1]: import sqlite_utils

In [2]: import sqlite3

In [3]: conn = sqlite3.connect(":memory:")

In [4]: conn
Out[4]: <sqlite3.Connection at 0x1087186c0>

In [5]: conn.executescript(""" ...: CREATE TABLE album( ...: albumartist TEXT, ...: albumname TEXT, ...: albumcover BINARY, ...: PRIMARY KEY(albumartist, albumname) ...: ); ...:
...: CREATE TABLE song( ...: songid INTEGER, ...: songartist TEXT, ...: songalbum TEXT, ...: songname TEXT, ...: FOREIGN KEY(songartist, songalbum) REFERENCES album(albumartist, albumname) ...: ); ...: """)
Out[5]: <sqlite3.Cursor at 0x1088def10>

In [6]: db = sqlite_utils.Database(conn)

In [7]: db.tables
Out[7]: [<Table album (albumartist, albumname, albumcover)>, <Table song (songid, songartist, songalbum, songname)>] In [8]: db.tables[0].foreign_keys Out[8]: [] In [9]: db.tables[1].foreign_keys Out[9]: [ForeignKey(table='song', column='songartist', other_table='album', other_column='albumartist'), ForeignKey(table='song', column='songalbum', other_table='album', other_column='albumname')] ``` The table appears to have two separate foreign keys, when actually it has a single compound composite foreign key.

openSUSE 15.1 is using python 3.6.5 and click-7.0 , however it has test failures while openSUSE Tumbleweed on py37 passes.

Most fail on the cli exit code like py [ 74s] =================================== FAILURES =================================== [ 74s] _________________________________ test_tables __________________________________ [ 74s] [ 74s] db_path = '/tmp/pytest-of-abuild/pytest-0/test_tables0/test.db' [ 74s] [ 74s] def test_tables(db_path): [ 74s] result = CliRunner().invoke(cli.cli, ["tables", db_path]) [ 74s] > assert '[{"table": "Gosh"},\n {"table": "Gosh2"}]' == result.output.strip() [ 74s] E assert '[{"table": "...e": "Gosh2"}]' == '' [ 74s] E - [{"table": "Gosh"}, [ 74s] E - {"table": "Gosh2"}] [ 74s] [ 74s] tests/test_cli.py:28: AssertionError

packaging project at https://build.opensuse.org/package/show/home:jayvdb:py-new/python-sqlite-utils

I'll keep digging into this after I have github-to-sqlite working on Tumbleweed, as I'll need openSUSE Leap 15.1 working before I can submit this into the main python repo.