While going through the documentation of Python’s sqlite31 module, I noticed that it’s quite API-driven, where different parts of the module are explained in a prescriptive manner. I, however, learn better from examples, recipes, and narratives. Although a few good recipes already exist in the docs, I thought I’d also enlist some of the examples I tried out while grokking them.

Executing individual statements

To execute individual statements, you’ll need to use the cursor_obj.execute(statement) primitive.

# src.py
import sqlite3

conn = sqlite3.connect(":memory:")
c = conn.cursor()

with conn:
    c.execute(
        """
    create table if not exists
        stat (id integer primary key, cat text, score real);
    """
    )

    c.execute("""insert into stat (cat, score) values ('a', 1.0);""")
    c.execute("""insert into stat (cat, score) values ('b', 2.0);""")
    result = c.execute("""select * from stat;""").fetchall()

    print(result)
[(1, 'a', 1.0), (2, 'b', 2.0)]

Executing batch statements

You can bundle up multiple statements and execute them in a single go with the cursor_obj.executemany(template_statement, (data, ...)) API.

# src.py
import sqlite3

conn = sqlite3.connect(":memory:")
c = conn.cursor()

with conn:
    c.execute(
        """
    create table if not exists
        stat (id integer primary key, cat text, score real);
    """
    )

    # Data needs to be passed as an iterable of tuples.
    data = (
        ("a", 1.0),
        ("b", 2.0),
        ("c", 3.0),
    )
    c.executemany("insert into stat (cat, score) values (?, ?);", data)
    result = c.execute("""select * from stat;""").fetchall()

    print(result)
[(1, 'a', 1.0), (2, 'b', 2.0), (3, 'c', 3.0)]

Applying user-defined callbacks

You can define and apply arbitrary Python callbacks to different data points in an SQLite table. There are two types of callbacks that you can apply:

  • Scalar function: A scalar function returns one value per invocation; in most cases, you can think of this as returning one value per row.

  • Aggregate function: In contrast, an aggregate function returns one value per group of rows.

Applying user-defined scalar functions

In the following example, I’ve created a table called users with two text type columns—username and password. Here, we define a transformation scalar function named sha256 that applies sha256 hashing to all the elements of the password column. The function is then registered via the connection_obj.create_function(func_name, narg, func) API.

# src.py
import sqlite3
import hashlib

conn = sqlite3.connect(":memory:")
c = conn.cursor()


def sha256(t: str) -> str:
    return hashlib.sha256(
        t.encode("utf-8"),
        usedforsecurity=True,
    ).hexdigest()


# Register the scalar function.
conn.create_function("sha256", 1, sha256)

with conn:
    c.execute(
        """
        create table if not exists users (
            username text,
            password text
        );
    """
    )
    c.execute(
        "insert into users values (?, sha256(?));",
        ("admin", "password"),
    )
    c.execute(
        "insert into users values (?, sha256(?));",
        ("user", "otherpass"),
    )

    result = c.execute("select * from users;").fetchall()
    print(result)
[
    (
        'admin',
        '5e884898da28047151d0e56f8dc6292773603d0d6aabbdd62a11ef721d1542d8'),
    (
        'user',
        '0da86a02c6944c679c5a7f06418bfde6bddb445de708639a3131af3682b34108'
    )
]

Applying user-defined aggregate functions

Aggregate functions are defined as classes and then registered with the connection_obj.create_aggregate(func_name, narg, aggregate_class) API. In the example below, I’ve created a table called series with a single integer type column val. To define an aggregate function, we’ll need to write a class with two methods—step and finalize where step will return the value of an intermediary progression step and finalize will return the final result. Below, you can see that the aggregate function returns a single value in the output.

# src.py
import sqlite3
import hashlib

conn = sqlite3.connect(":memory:")
c = conn.cursor()


class Mult:
    def __init__(self):
        self._result = 1

    def step(self, value):
        self._result *= value

    def finalize(self):
        return self._result


# Register the aggregate class.
conn.create_aggregate("mult", 1, Mult)

with conn:
    c.execute(
        """
        create table if not exists series (
            val integer
        );
    """
    )
    c.execute("insert into series (val) values (?);", (2,))
    c.execute("insert into series (val) values (?);", (3,))

    result = c.execute("select mult(val) from series;").fetchall()
    print(result)
[(6,)]

Printing traceback when a user-defined callback raises an error

By default, sqlite3 will suppress the traceback of any error raised from an user-defined function. However, you can turn on the traceback option as follows:

# src
import sqlite3

sqlite3.enable_callback_tracebacks(True)

...

Transforming types

Conventionally, Python sqlite3 documentation uses the term adaptation to refer to the transformation that changes Python types to SQLite types and conversion to refer to the change in the reverse direction.

Adapting Python types to SQLite types

To transform Python types to native SQLite types, you’ll need to define a transformation callback that’ll carry out the task. Then the callback will need to be registered with the sqlite3.register_adapter(type, adapter_callback) API.

Here, I’ve created an in-memory table called colors with a single text type column name that refers to the name of the color. Then I register the lambda color: color.value anonymous function that serializes an enum value to a text value. This allows me to pass an enum member directly into the cursor_obj.execute method.

# src.py
import enum
import sqlite3

conn = sqlite3.connect(":memory:")
c = conn.cursor()


class Color(enum.Enum):
    RED = "red"
    GREEN = "green"
    BLUE = "blue"


# Register an adapter to transform a Python type to an SQLite type.
sqlite3.register_adapter(Color, lambda color: color.value)

with conn:
    c.execute(
        """
        create table if not exists colors (
            name integer
        );
    """
    )
    c.execute("insert into colors (name) values (?);", (Color.RED,))
    c.execute("insert into colors (name) values (?);", (Color.GREEN,))

    result = c.execute("select name from colors;").fetchall()
    print(result)
[('red',), ('green',)]

Converting SQLite types to Python types

Converting SQLite types to Python types works similarly to the previous section. Here, as well, I’ve created the same colors table with a single name column as before. But this time, I want to insert string values into the name column and get back native enum objects from that field while performing a get query.

To do so, I’ve registered a converter function with the sqlite3.register_converter("sqlite_type_as_a_string", converter_callback) API. Another point to keep in mind is that you’ll have to set detect_type=sqlite3.PARSE_DECLTYPES in the sqlite3.connection method for the adaptation to work. Notice the output of the last select ... statement and you’ll see that we’re getting enum objects in the returned list.

# src.py
import enum
import sqlite3


class Color(enum.Enum):
    RED = "red"
    GREEN = "green"
    BLUE = "blue"


color_map = {v.value: v for v in Color.__members__.values()}

# Register a convert to convert text to Color enum
sqlite3.register_converter(
    "text",
    lambda v: color_map[v.decode("utf-8")],
)

conn = sqlite3.connect(
    ":memory:",
    detect_types=sqlite3.PARSE_DECLTYPES,  # Parse declaration types.
)

c = conn.cursor()

with conn:
    c.execute(
        """
        create table if not exists colors (
            name text
        );
    """
    )
    c.execute("insert into colors (name) values (?);", ("red",))
    c.execute("insert into colors (name) values (?);", ("green",))
    c.execute("insert into colors (name) values (?);", ("blue",))

    result = c.execute("select name from colors;").fetchall()
    print(result)
[
    (<Color.RED: 'red'>,),
    (<Color.GREEN: 'green'>,),
    (<Color.BLUE: 'blue'>,)
]

Using the default adapters and converters

The sqlite3 module also employs some default adapters and converters that you can take advantage of without defining and registering custom transformers. For example, SQLite doesn’t have any special types to represent a date or timestamp. However, Python sqlite3 allows you to annotate a column with a special type and it’ll automatically convert the values of the column to a compatible type of Python object while returning the result of a get query.

Here, I’ve created a table called timekeeper with two columns—d and dt where d expects a date and dt expects a timestamp. So, in the table creation DDL statement, we annotate the columns with date and timestamp types respectively. We’ve also turned on column type parsing by setting detect_types=sqlite3.PARSE_DECLTYPES | sqlite3.PARSE_COLNAMES in the sqlite3.connect method.

Finally, notice how we’re inserting datetime.date and datetime.datetime objects directly into the table. Also, this time, the final select ... statement looks a bit different. We’re specifying the expected type in the select ... statement and it’s returning native Python objects in the returned list.

# src.py
import datetime
import sqlite3
import zoneinfo

conn = sqlite3.connect(
    ":memory:",
    detect_types=sqlite3.PARSE_DECLTYPES | sqlite3.PARSE_COLNAMES,
)

with conn:
    c = conn.cursor()
    c.execute(
        """
        create table if not exists
        timekeeper (id integer primary key, d date, dt timestamp);"""
    )
    tz = zoneinfo.ZoneInfo("America/New_York")
    dt = datetime.datetime.now(tz)
    d = dt.date()

    c.execute(
        "insert into timekeeper (d, dt) values (?, ?);",
        ((d, dt)),
    )
    result = c.execute(
        """
        select
            d as "d [date]", dt as "dt [timestamp]"
            from timekeeper;"""
    ).fetchall()
    print(result)
[
    (
        datetime.date(2022, 9, 5),
        datetime.datetime(2022, 9, 5, 14, 59, 52, 867917)
    )
]

Implementing authorization control

Sometimes you need control over what operations are allowed to be run on an SQLite database and what aren’t. The connection_obj.set_authorizer(auth_callback) allows you to implement authorization control. Here, auth_callback takes in 5 arguments. From the docs:

The 1st argument to the callback signifies what kind of operation is to be authorized. The 2nd and 3rd arguments will be arguments or None depending on the 1st argument. The 4th argument is the name of the database (“main”, “temp”, etc.) if applicable. The 5th argument is the name of the inner-most trigger or view that is responsible for the access attempt or None if this access attempt is directly from input SQL code. Please consult the SQLite documentation about the possible values for the first argument and the meaning of the second and third arguments depending on the first one.

You can find the list of all the supported actions here2. In the following example, I’m disallowing create table, create index, drop table, and drop index actions. To deny an action, the auth_callback will have to return sqlite3.SQLITE_DENY and that’ll raise an sqlite3.DatabaseError exception whenever a user tries to execute any of the restricted actions. Returning sqlite3.SQLITE_OK from the callback ensures that unfiltered actions can still pass through the guardrail without incurring any errors.

# src.py
import sqlite3

conn = sqlite3.connect(":memory:")


def authorizer(action, arg1, arg2, dbname, trigger):
    # Print the params.
    print(action, arg1, arg2, dbname, trigger)

    # Disallow these actions.
    if action in (
        sqlite3.SQLITE_CREATE_TABLE,
        sqlite3.SQLITE_CREATE_INDEX,
        sqlite3.SQLITE_DROP_TABLE,
        sqlite3.SQLITE_DROP_INDEX,
    ):
        return sqlite3.SQLITE_DENY

    # Let everything else pass through.
    return sqlite3.SQLITE_OK


c = conn.cursor()

with conn:
    c.execute(
        """
        create table if not exists colors (
            name text
        );
    """
    )
    # After creating the table, let's make sure users can't perform
    # certain DDL operations.
    conn.set_authorizer(authorizer)

    c.execute("insert into colors (name) values (?);", ("red",))

    # This will fail because the authorizer will deny the operation.
    c.execute("drop table colors;")
18 colors None main None
22 BEGIN None None None
9 sqlite_master None main None
11 colors None main None
22 ROLLBACK None None None
Traceback (most recent call last):
  File "/home/rednafi/canvas/personal/reflections/src.py", line 45, in <module>
    c.execute("drop table colors;")
sqlite3.DatabaseError: not authorized

Changing the representation of a row

The sqlite3 module allows you to change the representation of a database row to your liking. By default, the result of a query comes out as a list of tuples where each tuple represents a single row. However, you can change the representation of database rows in such a way that the result might come out as a list of dictionaries or a list of custom objects.

Via an arbitrary container object as the row factory

You can attach a callback to the connection_obj.row_factory attribute to change how you want to display the rows in a result list. The factory callback takes in two arguments— cursor and row where cursor is a tuple containing some metadata related to a single table record and row is the default representation of a single database row as a tuple.

In the following snippet, just like before, I’m creating the same colors table with two columns—name and hex. Here, the row_factory function is the factory callback that converts the default row representation from a tuple to a dictionary. We’re then registering the row_factory function with the connection_obj.row_factory = row_factory assignment statement. Afterward, the sqlite3 module calls this statement on each record and transforms the representation of the rows. When you run the snippet, you’ll see that the result comes out as a list of dictionaries instead of a list of tuples.

# src.py
import sqlite3


conn = sqlite3.connect(":memory:")


# Using a dictionary to represent a row.
def row_factory(cursor, row):
    # cursor.description:
    # (name, type_code, display_size,
    # internal_size, precision, scale, null_ok)
    # row: (value, value, ...)
    return {
        col[0]: row[idx]
        for idx, col in enumerate(
            cursor.description,
        )
    }


conn.row_factory = row_factory

c = conn.cursor()

with conn:
    c.execute(
        """
        create table if not exists colors (
            name text,
            hex text
        );
    """
    )

    c.execute(
        "insert into colors (name, hex) values (?, ?);",
        ("red", "#ff0000"),
    )
    c.execute(
        "insert into colors (name, hex) values (?, ?);",
        ("green", "#00ff00"),
    )
    c.execute(
        "insert into colors (name, hex) values (?, ?);",
        ("blue", "#0000ff"),
    )

    result = c.execute("select * from colors;").fetchall()
    print(result)
[
    {'name': 'red', 'hex': '#ff0000'},
    {'name': 'green', 'hex': '#00ff00'},
    {'name': 'blue', 'hex': '#0000ff'}
]

Via a specialized Row object as the row factory

Instead of rolling with your own custom row factory, you can also take advantage of the highly optimized sqlite3.Row object. From the docs:

A Row instance serves as a highly optimized row_factory for Connection objects. It supports iteration, equality testing, len(), and mapping access by column name and index. Two row objects compare equal if have equal columns and equal members.

In the following example, I’ve reused the script from the previous section and just replaced the custom row factory callback with sqlite3.Row. In the output, you’ll see that the Row object not only allows us to access the value of a column by row[column_name] syntax but also let us convert the representation of the final result.

# src.py
import sqlite3

conn = sqlite3.connect(":memory:")

# Registering a highly optimized 'Row' object as the
# default row_factory. Row is a map-like object that
# allows you to access column values by name.
conn.row_factory = sqlite3.Row

c = conn.cursor()

with conn:
    c.execute(
        """
        create table if not exists colors (
            name text,
            hex text
        );
    """
    )

    c.executemany(
        "insert into colors (name, hex) values (?, ?);",
        (
            ("red", "#ff0000"),
            ("green", "#00ff00"),
            ("blue", "#0000ff"),
        ),
    )

    result = c.execute("select * from colors;").fetchall()

    # Access the values of a row by column name.
    for row in result:
        print(row["name"], row["hex"])

    # Convert the result to a list of dicts.
    result_dict = [dict(row) for row in result]
    print(result_dict)
red #ff0000
green #00ff00
blue #0000ff
[
    {'name': 'red', 'hex': '#ff0000'},
    {'name': 'green', 'hex': '#00ff00'},
    {'name': 'blue', 'hex': '#0000ff'}
]

Via text factory

If you need to apply a common transformation callback to multiple text columns, the sqlite3 module has a shortcut to do so. You can certainly write an ordinary row factory that’ll only transform the text columns but the connection_obj.text_factory attribute enables you to do that in a more elegant fashion. You can set connection_obj.text_factory = row_factory and that’ll selectively apply the row_factory callback only to the text columns. In the following example, I’m applying an anonymous function to the text columns to translate the color names to English.

# src.py
import sqlite3


conn = sqlite3.connect(":memory:")

c = conn.cursor()

# Apply factory only to text fields.
color_map = {"το κόκκινο": "red", "সবুজ": "green"}

# Translate all the text fields.
conn.text_factory = lambda x: color_map.get(x.decode("utf-8"), x)

with conn:
    c.execute("create table if not exists colors (name text);")

    c.execute("insert into colors (name) values (?);", ("το κόκκινο",))
    c.execute("insert into colors (name) values (?);", ("সবুজ",))

    result = c.execute("select * from colors;").fetchall()
    print(result)
[('red',), ('green',)]

Creating custom collation

Collation defines how the string values in a text column are compared. It also dictates how the data in the column will be ordered when you perform any kind of sort operation. A collation callback can be registered with the connection_obj.create_collation(name, collation_callback) syntax where the name denotes the name of the collation rule and the collation_callback determines how the string comparison should be done. The callback accepts two string values as arguments and returns:

  • 1 if the first is ordered higher than the second
  • -1 if the first is ordered lower than the second
  • 0 if they are ordered equal

Then you can use the collation rules with an order by clause as follows:

select * from table_name order by column_name collate collation_name

Here’s a full example of a collation callback in action:

# src.py
import sqlite3

conn = sqlite3.connect(":memory:")

c = conn.cursor()


def reverse_collate(a, b):
    return 1 if a < b else -1 if a > b else 0


# Register the collation function.
conn.create_collation("reverse", reverse_collate)

with conn:
    c.execute("create table if not exists colors (name text);")

    c.executemany(
        "insert into colors (name) values (?);",
        (("το κόκκινο",), ("সবুজ",)),
    )

    result = c.execute(
        """select * from colors
            order by name collate reverse;"""
    ).fetchall()
    print(result)
[('সবুজ',), ('το κόκκινο',)]

Registering trace callbacks to introspect running SQL statements

During debugging, I often find it helpful to be able to trace all the SQL statements running under a certain connection. This becomes even more useful in a multiprocessing environment where each process opens a new connection to the DB and runs its own sets of SQL queries. We can leverage the connection_obj.set_trace_callback method to trace the statements. The set_trace_callback method accepts a callable that takes a single argument and sqlite3 module passes the currently running statement to the callback every time it invokes it. Notice how the output prints all the statements executed by SQLite behind the scene. This also reveals that cursor_obj.executemany wraps up multiple statements in a transaction and runs them in an atomic manner.

# src.py
import sqlite3

conn = sqlite3.connect(":memory:")

c = conn.cursor()


# Print all the statements executed.
def introspect(s):
    print(s)


# Register the trace function.
conn.set_trace_callback(introspect)

with conn:
    c.execute("create table if not exists colors (name text);")

    c.executemany(
        "insert into colors (name) values (?);",
        (("red",), ("green",), ("blue",)),
    )

    result = c.execute("""select * from colors""").fetchall()
    print(result)
create table if not exists colors (name text);
BEGIN
insert into colors (name) values (?);
insert into colors (name) values (?);
insert into colors (name) values (?);
select * from colors
[('red',), ('green',), ('blue',)]
COMMIT

Backing up a database

There are a few ways you can back up your database file via Python sqlite3.

Dumping the database iteratively

The following snippet creates a table, inserts some data into it, and then, iteratively fetches the database content via the connection_obj.iterdump() API. Afterward, the returned content is written to another database file using the file.write primitive.

For demonstration purposes, I’m using an in-memory DB and backing that up in another NamedTemporaryFile. This will work the same way with an on-disk DB and on-disk backup file as well. One advantage of this approach is that your data is not loaded into memory at once, rather it’s streamed iteratively from the main DB to the backup DB.

# src.py
import sqlite3
import tempfile
from contextlib import ExitStack

conn = sqlite3.connect(":memory:")

with ExitStack() as stack:
    conn = stack.enter_context(conn)
    dst_file = stack.enter_context(tempfile.NamedTemporaryFile())

    c = conn.cursor()
    c.execute("create table if not exists colors (name text);")
    c.executemany(
        "insert into colors (name) values (?);",
        (("red",), ("green",), ("blue",)),
    )

    for line in conn.iterdump():
        dst_file.write(line.encode("utf-8") + b"\n")

    dst_file.seek(0)
    print(dst_file.read().decode("utf-8"))
BEGIN TRANSACTION;
CREATE TABLE colors (name text);
INSERT INTO "colors" VALUES('red');
INSERT INTO "colors" VALUES('green');
INSERT INTO "colors" VALUES('blue');
COMMIT;

Copying an on-disk database to another

This example shows another approach that you can adopt to create a second copy of your on-disk DB. First, it connects to the source DB and then creates another connection to an empty backup DB. Afterward, the source data is backed up to the destination DB with the connection_obj_source.backup(connection_obj_destination) API.

The .backup method takes in three values—a connection object that points to the destination DB, the number of pages to copy in a single pass, and a callback to introspect the progress. You can set the value of the progress parameter to -1 if you want to load the entire source database into memory and copy everything to the destination in a single pass. Also, in this example, the progress hook just prints the progress of the copied pages.

# src.py
import sqlite3
from contextlib import ExitStack

conn_src = sqlite3.connect("src.db")
conn_dst = sqlite3.connect("dst.db")


# Hook that indicates backup progress.
def progress(status, remaining, total):
    print(f"Copied {total-remaining} of {total} pages...")


with ExitStack() as stack:
    conn_src = stack.enter_context(conn_src)
    conn_dst = stack.enter_context(conn_dst)

    cursor_src = conn_src.cursor()

    cursor_src.execute(
        """
        create table if not exists colors (
            name text,
            hex text
        );
    """
    )

    cursor_src.executemany(
        "insert into colors (name, hex) values (?, ?);",
        (
            ("red", "#ff0000"),
            ("green", "#00ff00"),
            ("blue", "#0000ff"),
        ),
    )

    # Must commit before backup.
    conn_src.commit()

    # Copy a to b. The 'pages' parameter determines how many DB pages
    # to copy in a single iteration. Set to -1 to load everything into
    # memory at once and do it in a single iteration.
    conn_src.backup(conn_dst, pages=1, progress=progress)

    # Ensure that the backup is complete.
    result = conn_dst.execute("select count(*) from colors;").fetchone()
    print(f"Number of rows in dst: {result[0]}")
Copied 1 of 2 pages...
Copied 2 of 2 pages...
Number of rows in dst: 3

Loading an on-disk database into the memory

The connection_obj.backup API also lets you load your existing database into memory. This is helpful when the DB you’re working with is small and you want to leverage the extra performance benefits that come with an in-memory DB. The workflow is almost exactly the same as before and the only difference is that the destination connection object points to an in-memory DB instead of an on-disk one.

# src.py
import sqlite3

conn_src = sqlite3.connect("src.db")
conn_dst = sqlite3.connect(":memory:")

with conn_src:
    cursor_src = conn_src.cursor()

    cursor_src.execute(
        """
        create table if not exists colors (
            name text,
            hex text
        );
    """
    )

    cursor_src.executemany(
        "insert into colors (name, hex) values (?, ?);",
        (
            ("red", "#ff0000"),
            ("green", "#00ff00"),
            ("blue", "#0000ff"),
        ),
    )

    # Must commit before backup.
    conn_src.commit()

    # Copy a to memory.
    conn_src.backup(conn_dst)

    # Ensure that the backup is complete.
    result = conn_dst.execute("select count(*) from colors;").fetchone()
    print(f"Number of rows in dst: {result[0]}")
Number of rows in dst: 3

Copying an in-memory database to an on-disk file

You can also dump your in-memory DB into the disk. Just point the source connection object to the in-memory DB and the destination connection to the on-disk DB file.

# src.py
import sqlite3

conn_src = sqlite3.connect(":memory:")
conn_dst = sqlite3.connect("dst.db")

with conn_src:
    cursor_src = conn_src.cursor()

    cursor_src.execute(
        """
        create table if not exists colors (
            name text,
            hex text
        );
    """
    )

    cursor_src.executemany(
        "insert into colors (name, hex) values (?, ?);",
        (
            ("red", "#ff0000"),
            ("green", "#00ff00"),
            ("blue", "#0000ff"),
        ),
    )

    # Must commit before backup.
    conn_src.commit()

    # Copy a to an on-disk file.
    conn_src.backup(conn_dst)

    # Ensure that the backup is complete.
    result = conn_dst.execute("select count(*) from colors;").fetchone()
    print(f"Number of rows in dst: {result[0]}")
Number of rows in dst: 3

Implementing a full text search engine

This is not exactly a feature that’s specific to the sqlite3 API. However, I wanted to showcase how effortless it is to leverage SQLite’s native features via the Python API. The following example creates a virtual table and implements a full-text search engine that allows us to fuzzy search the colors in the colors table by their names or hex values.

# src.py
import sqlite3
import uuid

conn = sqlite3.connect(":memory:")

# Get the search result as a Python dict.
conn.row_factory = lambda cursor, row: {
    col[0]: row[idx] for idx, col in enumerate(cursor.description)
}

with conn:
    c = conn.cursor()

    # Unindexed ensures that uuid field doesn't appear in the ft5 index.
    c.execute(
        """
        create virtual table
        if not exists colors using fts5(uuid unindexed, name, hex);"""
    )
    get_uuid = lambda: str(uuid.uuid4())  # noqa: E731

    color_data = (
        (get_uuid(), "red", "#ff0000"),
        (get_uuid(), "green", "#00ff00"),
        (get_uuid(), "blue", "#0000ff"),
        (get_uuid(), "yellow", "#ffff00"),
        (get_uuid(), "cyan", "#00ffff"),
        (get_uuid(), "magenta", "#ff00ff"),
        (get_uuid(), "black", "#000000"),
        (get_uuid(), "white", "#ffffff"),
    )
    c.executemany("insert into colors values (?, ?, ?);", color_data)
    result = c.execute(
        """select * from colors where name match
            'cyan OR red NOT magenta';"""
    ).fetchall()
    print(result)
[
    {
        'uuid': 'c5f6e5ea-124b-44fe-afad-69aad565541e',
        'name': 'red',
        'hex': '#ff0000'

    },
    {
        'uuid': '0dedbb75-6e1d-4a7f-85f7-f0ed0ae4d162',
        'name': 'cyan',
        'hex': '#00ffff'
    }
]

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