PARTITION KEY support (#122)

* initial pass at PARTITION KEY support.

* unit tests

* gha this PR branch

* fixup tests

* doc internal

* fix tests, KNN/rowids in

* define SQLITE_INDEX_CONSTRAINT_OFFSET

* whoops

* update tests, syrupy, use uv

* un ignore pyproject.toml

* dot

* tests/

* type error?

* win: .exe, update error name

* try fix macos python, paren around expr?

* win bash?

* dbg :(

* explicit error

* op

* dbg win

* win ./tests/.venv/Scripts/python.exe

* block UPDATEs on partition key values for now

tests/test-partition-keys.py

@@ -0,0 +1,115 @@
+import sqlite3
+from collections import OrderedDict
+
+
+def test_constructor_limit(db, snapshot):
+    assert exec(
+        db,
+        """
+        create virtual table v using vec0(
+          p1 int partition key,
+          p2 int partition key,
+          p3 int partition key,
+          p4 int partition key,
+          p5 int partition key,
+          v float[1]
+        )
+      """,
+    ) == snapshot(name="max 4 partition keys")
+
+
+def test_normal(db, snapshot):
+    db.execute(
+        "create virtual table v using vec0(p1 int partition key, a float[1], chunk_size=8)"
+    )
+
+    db.execute("insert into v(rowid, p1, a) values (1, 100, X'11223344')")
+    assert vec0_shadow_table_contents(db, "v") == snapshot(name="1 row")
+    db.execute("insert into v(rowid, p1, a) values (2, 100, X'44556677')")
+    assert vec0_shadow_table_contents(db, "v") == snapshot(name="2 rows, same parition")
+    db.execute("insert into v(rowid, p1, a) values (3, 200, X'8899aabb')")
+    assert vec0_shadow_table_contents(db, "v") == snapshot(name="3 rows, 2 partitions")
+
+
+def test_types(db, snapshot):
+    db.execute(
+        "create virtual table v using vec0(p1 int partition key, a float[1], chunk_size=8)"
+    )
+
+    # EVIDENCE-OF: V11454_28292
+    assert exec(
+        db, "insert into v(p1, a) values(?, ?)", ["not int", b"\x11\x22\x33\x44"]
+    ) == snapshot(name="1. raises type error")
+
+    assert vec0_shadow_table_contents(db, "v") == snapshot(name="2. empty DB")
+
+    # but allow NULLs
+    assert exec(
+        db, "insert into v(p1, a) values(?, ?)", [None, b"\x11\x22\x33\x44"]
+    ) == snapshot(name="3. allow nulls")
+
+    assert vec0_shadow_table_contents(db, "v") == snapshot(
+        name="4. show NULL partition key"
+    )
+
+
+def test_updates(db, snapshot):
+    db.execute(
+        "create virtual table v using vec0(p text partition key, a float[1], chunk_size=8)"
+    )
+
+    db.execute(
+        "insert into v(rowid, p, a) values (?, ?, ?)", [1, "a", b"\x11\x11\x11\x11"]
+    )
+    db.execute(
+        "insert into v(rowid, p, a) values (?, ?, ?)", [2, "a", b"\x22\x22\x22\x22"]
+    )
+    db.execute(
+        "insert into v(rowid, p, a) values (?, ?, ?)", [3, "a", b"\x33\x33\x33\x33"]
+    )
+
+    assert exec(db, "select * from v") == snapshot(name="1. Initial dataset")
+    assert exec(db, "update v set p = ? where rowid = ?", ["new", 1]) == snapshot(
+        name="2. update #1"
+    )
+
+
+class Row:
+    def __init__(self):
+        pass
+
+    def __repr__(self) -> str:
+        return repr()
+
+
+def exec(db, sql, parameters=[]):
+    try:
+        rows = db.execute(sql, parameters).fetchall()
+    except (sqlite3.OperationalError, sqlite3.DatabaseError) as e:
+        return {
+            "error": e.__class__.__name__,
+            "message": str(e),
+        }
+    a = []
+    for row in rows:
+        o = OrderedDict()
+        for k in row.keys():
+            o[k] = row[k]
+        a.append(o)
+    result = OrderedDict()
+    result["sql"] = sql
+    result["rows"] = a
+    return result
+
+
+def vec0_shadow_table_contents(db, v):
+    shadow_tables = [
+        row[0]
+        for row in db.execute(
+            "select name from sqlite_master where name like ? order by 1", [f"{v}_%"]
+        ).fetchall()
+    ]
+    o = {}
+    for shadow_table in shadow_tables:
+        o[shadow_table] = exec(db, f"select * from {shadow_table}")
+    return o