Merge pull request #9 from CrispenGari/query-builder

query builder and the doccumentation

Author: CrispenGari

Changelog.md

@@ -1,10 +1,44 @@
+===
+Dataloom **`2.3.0`**
+===
+
+### Release Notes - `dataloom`
+
+We have release the new `dataloom` Version `2.3.0` (`2024-02-26`)
+
+##### Features
+
+- updated documentation.
+- Query Builder in executing queries and SQL Scripts.
+
+```py
+qb = loom.getQueryBuilder()
+res = qb.run("select id from posts;", fetchall=True)
+print(res)
+```
+
+We can use the query builder to execute the SQL as follows:
+
+```py
+with open("qb.sql", "r") as reader:
+    sql = reader.read()
+res = qb.run(
+    sql,
+    fetchall=True,
+    is_script=True,
+)
+print(res)
+```
+
+> 👍 **Pro Tip:** Executing a script using query builder does not return a result. The result value is always `None`.
+
 ===
 Dataloom **`2.2.0`**
 ===
 
 ### Release Notes - `dataloom`
 
-We have release the new `dataloom` Version `2.2.0` (`2024-02-24`)
+We have release the new `dataloom` Version `2.2.0` (`2024-02-25`)
 
 ##### Features
 

README.md

@@ -105,6 +105,8 @@
   - [4. What about bidirectional queries?](#4-what-about-bidirectional-queries)
     - [1. Child to Parent](#1-child-to-parent)
     - [2. Parent to Child](#2-parent-to-child)
+- [Query Builder.](#query-builder)
+  - [Why Use Query Builder?](#why-use-query-builder)
 - [What is coming next?](#what-is-coming-next)
 - [Contributing](#contributing)
 - [License](#license)
@@ -2112,10 +2114,81 @@ print(user_post) """ ? =
 
 ```
 
+### Query Builder.
+
+Dataloom exposes a method called `getQueryBuilder`, which allows you to obtain a `qb` object. This object enables you to execute SQL queries directly from SQL scripts.
+
+```py
+qb = loom.getQueryBuilder()
+
+print(qb) # ? = Loom QB<mysql>
+```
+
+The `qb` object contains the method called `run`, which is used to execute SQL scripts or SQL queries.
+
+```py
+ids = qb.run("select id from posts;", fetchall=True)
+print(ids) # ? = [(1,), (2,), (3,), (4,)]
+```
+
+You can also execute SQL files. In the following example, we will demonstrate how you can execute SQL scripts using the `qb`. Let's say we have an SQL file called `qb.sql` which contains the following SQL code:
+
+```SQL
+SELECT id, title FROM posts WHERE id IN (1, 3, 2, 4) LIMIT 4 OFFSET  1;
+SELECT COUNT(*) FROM (
+    SELECT DISTINCT `id`
+    FROM `posts`
+    WHERE `id` < 5
+    LIMIT 3 OFFSET 2
+) AS subquery;
+```
+
+We can use the query builder to execute the SQL as follows:
+
+```py
+with open("qb.sql", "r") as reader:
+    sql = reader.read()
+res = qb.run(
+    sql,
+    fetchall=True,
+    is_script=True,
+)
+print(res)
+```
+
+> 👍 **Pro Tip:** Executing a script using query builder does not return a result. The result value is always `None`.
+
+The `run` method takes the following as arguments:
+
+| Argument        | Description                                                                            | Type                                           | Required | Default |
+| --------------- | -------------------------------------------------------------------------------------- | ---------------------------------------------- | -------- | ------- |
+| `sql`           | SQL query to execute.                                                                  | `str`                                          | Yes      |         |
+| `args`          | Parameters for the SQL query.                                                          | `Any \| None`                                  | No       | `None`  |
+| `fetchone`      | Whether to fetch only one result.                                                      | `bool`                                         | No       | `False` |
+| `fetchmany`     | Whether to fetch multiple results.                                                     | `bool`                                         | No       | `False` |
+| `fetchall`      | Whether to fetch all results.                                                          | `bool`                                         | No       | `False` |
+| `mutation`      | Whether the query is a mutation (insert, update, delete).                              | `bool`                                         | No       | `True`  |
+| `bulk`          | Whether the query is a bulk operation.                                                 | `bool`                                         | No       | `False` |
+| `affected_rows` | Whether to return affected rows.                                                       | `bool`                                         | No       | `False` |
+| `operation`     | Type of operation being performed.                                                     | `'insert', 'update', 'delete', 'read' \| None` | No       | `None`  |
+| `verbose`       | Verbosity level for logging . Set this option to `0` if you don't want logging at all. | `int`                                          | No       | `1`     |
+| `is_script`     | Whether the SQL is a script.                                                           | `bool`                                         | No       | `False` |
+
+#### Why Use Query Builder?
+
+- The query builder empowers developers to seamlessly execute `SQL` queries directly.
+- While Dataloom primarily utilizes `subqueries` for eager data fetching on models, developers may prefer to employ JOIN operations, which are achievable through the `qb` object.
+
+  ```python
+  qb = loom.getQueryBuilder()
+  result = qb.run("SELECT * FROM table1 INNER JOIN table2 ON table1.id = table2.table1_id;")
+  print(result)
+  ```
+
 ### What is coming next?
 
 1. N-N associations
-2. Query Builder
+2. Self relations
 
 ### Contributing
 

dataloom/loom/__init__.py

@@ -12,7 +12,7 @@
 from dataloom.model import Model
 from dataloom.statements import GetStatement
 from dataloom.conn import ConnectionOptionsFactory
-from typing import Optional, Any
+from typing import Optional, Any, Literal
 from mysql.connector.pooling import PooledMySQLConnection
 from sqlite3 import Connection
 from mysql.connector.connection import MySQLConnectionAbstract
@@ -27,6 +27,7 @@
 )
 from dataloom.loom.interfaces import ILoom
 from dataloom.loom.math import math
+from dataloom.loom.qb import qb
 
 
 class Loom(ILoom):
@@ -1165,7 +1166,7 @@ def _execute_sql(
         mutation=True,
         bulk: bool = False,
         affected_rows: bool = False,
-        operation: Optional[str] = None,
+        operation: Optional[Literal["insert", "update", "delete", "read"]] = None,
         _verbose: int = 1,
         _is_script: bool = False,
     ) -> Any:
@@ -1785,3 +1786,28 @@ def count(
             distinct=distinct,
             filters=filters,
         )
+
+        # qb
+
+    def getQueryBuilder(self):
+        """
+        getQueryBuilder
+        ---------------
+        Retrieves a query builder instance.
+
+        Parameters
+        ----------
+        No parameters
+
+        Returns
+        -------
+        qb
+            Query builder instance.
+
+        Examples
+        --------
+        >>> qb = loom.getQueryBuilder()
+        ... print(qb)
+        """
+        builder = qb(_execute_sql=self._execute_sql, dialect=self.dialect)
+        return builder

dataloom/loom/interfaces.py

@@ -218,21 +218,6 @@ def delete_bulk(
     def tables(self):
         raise NotImplementedError("The tables property was not implemented")
 
-    @abstractclassmethod
-    def _execute_sql(
-        self,
-        sql: str,
-        args=None,
-        fetchone=False,
-        fetchmany=False,
-        fetchall=False,
-        mutation=True,
-        bulk: bool = False,
-        affected_rows: bool = False,
-        operation: Optional[str] = None,
-    ) -> Any:
-        raise NotImplementedError("The _execute_sql method was not implemented.")
-
     def connect(
         self,
     ) -> Any | PooledMySQLConnection | MySQLConnectionAbstract | Connection:

dataloom/loom/qb.py

@@ -0,0 +1,88 @@
+from typing import Callable, Any, Literal, Optional
+
+from dataloom.types import DIALECT_LITERAL
+
+
+class qb:
+    def __repr__(self) -> str:
+        return f"Loom QB<{self.dialect}>"
+
+    def __str__(self) -> str:
+        return f"Loom QB<{self.dialect}>"
+
+    def __init__(
+        self, _execute_sql: Callable[..., Any], dialect: DIALECT_LITERAL
+    ) -> None:
+        self.__exc = _execute_sql
+        self.dialect = dialect
+
+    def run(
+        self,
+        sql: str,
+        args: Any | None = None,
+        fetchone: bool = False,
+        fetchmany: bool = False,
+        fetchall: bool = False,
+        mutation: bool = True,
+        bulk: bool = False,
+        affected_rows: bool = False,
+        operation: Optional[Literal["insert", "update", "delete", "read"]] = None,
+        verbose: int = 1,
+        is_script: bool = False,
+    ):
+        """
+        run
+        -----------
+
+        Execute SQL query with optional parameters.
+
+        Parameters
+        ----------
+        sql : str
+            SQL query to execute.
+        args : Any | None, optional
+            Parameters for the SQL query. Defaults to None.
+        fetchone : bool, optional
+            Whether to fetch only one result. Defaults to False.
+        fetchmany : bool, optional
+            Whether to fetch multiple results. Defaults to False.
+        fetchall : bool, optional
+            Whether to fetch all results. Defaults to False.
+        mutation : bool, optional
+            Whether the query is a mutation (insert, update, delete). Defaults to True.
+        bulk : bool, optional
+            Whether the query is a bulk operation. Defaults to False.
+        affected_rows : bool, optional
+            Whether to return affected rows. Defaults to False.
+        operation : Literal['insert', 'update', 'delete', 'read'] | None, optional
+            Type of operation being performed. Defaults to None.
+        verbose : int, optional
+            Verbosity level for logging. Defaults to 1.
+        is_script : bool, optional
+            Whether the SQL is a script. Defaults to False.
+
+        Returns
+        -------
+        Any
+            Query result.
+
+        Examples
+        --------
+        >>> qb = loom.getQueryBuilder()
+        ... ids = qb.run("select id from posts;", fetchall=True)
+        ... print(ids)
+        ...
+        """
+        return self.__exc(
+            sql,
+            args=args,
+            fetchall=fetchall,
+            fetchmany=fetchmany,
+            fetchone=fetchone,
+            mutation=mutation,
+            bulk=bulk,
+            affected_rows=affected_rows,
+            operation=operation,
+            _verbose=verbose,
+            _is_script=is_script,
+        )

dataloom/loom/sql.py

@@ -1,4 +1,4 @@
-from typing import Any, Optional
+from typing import Any, Optional, Literal
 from dataloom.types import DIALECT_LITERAL, SQL_LOGGER_LITERAL
 from dataloom.exceptions import UnsupportedDialectException
 from sqlite3 import Connection
@@ -59,7 +59,7 @@ def execute_sql(
         mutation=True,
         bulk: bool = False,
         affected_rows: bool = False,
-        operation: Optional[str] = None,
+        operation: Optional[Literal["insert", "update", "delete", "read"]] = None,
         _verbose: int = 1,
         _is_script: bool = False,
     ) -> Any:
@@ -110,7 +110,6 @@ def execute_sql(
                         except Exception:
                             pass
                     return None
-
                 if args is None:
                     cursor.execute(sql)
                 else:

dataloom/tests/mysql/test_qb_mysql.py

@@ -0,0 +1,63 @@
+class TestQBMySQL:
+    def test_qb(self):
+        from dataloom import (
+            Loom,
+            Model,
+            Column,
+            PrimaryKeyColumn,
+            CreatedAtColumn,
+            UpdatedAtColumn,
+            TableColumn,
+            ForeignKeyColumn,
+            ColumnValue,
+        )
+        from dataloom.keys import MySQLConfig
+        from typing import Optional
+
+        mysql_loom = Loom(
+            dialect="mysql",
+            database=MySQLConfig.database,
+            password=MySQLConfig.password,
+            user=MySQLConfig.user,
+        )
+
+        class User(Model):
+            __tablename__: Optional[TableColumn] = TableColumn(name="users")
+            id = PrimaryKeyColumn(type="int", auto_increment=True)
+            name = Column(type="text", nullable=False, default="Bob")
+            username = Column(type="varchar", unique=True, length=255)
+
+        class Post(Model):
+            __tablename__: Optional[TableColumn] = TableColumn(name="posts")
+            id = PrimaryKeyColumn(
+                type="int", auto_increment=True, nullable=False, unique=True
+            )
+            completed = Column(type="boolean", default=False)
+            title = Column(type="varchar", length=255, nullable=False)
+            # timestamps
+            createdAt = CreatedAtColumn()
+            updatedAt = UpdatedAtColumn()
+            # relations
+            userId = ForeignKeyColumn(
+                User, type="int", required=True, onDelete="CASCADE", onUpdate="CASCADE"
+            )
+
+        conn, _ = mysql_loom.connect_and_sync([Post, User], drop=True, force=True)
+        userId = mysql_loom.insert_one(
+            instance=User,
+            values=ColumnValue(name="username", value="@miller"),
+        )
+
+        for title in ["Hey", "Hello", "What are you doing", "Coding"]:
+            mysql_loom.insert_one(
+                instance=Post,
+                values=[
+                    ColumnValue(name="userId", value=userId),
+                    ColumnValue(name="title", value=title),
+                ],
+            )
+        qb = mysql_loom.getQueryBuilder()
+        res = qb.run("select id from posts;", fetchall=True)
+        assert str(qb) == "Loom QB<mysql>"
+        assert len(res) == 4
+        conn.close()