Add sqlite3/README.md

sqlite3/README.md

@@ -0,0 +1,78 @@
+## Better Python interface for `sqlite3`
+
+```python
+import sqlite3, json
+
+class DB(sqlite3.Connection):
+    def __init__(self, db_name="db.sqlite"):
+        super().__init__(db_name)
+        with self:
+            self.execute('''
+                CREATE TABLE IF NOT EXISTS kv_store
+                (key TEXT PRIMARY KEY, value BLOB)
+            ''')
+
+    def __setitem__(self, key, value):
+        if not isinstance(value, bytes):
+            value = json.dumps(value)
+        with self:
+            cur = self.execute('''
+                INSERT OR REPLACE INTO kv_store
+                (key, value) VALUES (?, ?)
+            ''', (key, value))
+            return {"modified_count": cur.rowcount}
+
+    def __getitem__(self, key):
+        with self:
+            result = self.execute('''
+                SELECT value FROM kv_store
+                WHERE key = ?
+            ''', (key,)).fetchone()
+        if result:
+            if isinstance(result[0], str):
+                try: return json.loads(result[0])
+                except: pass
+            return result[0]
+
+    def delete(self, key):
+        with self:
+            cur = self.execute('''
+                DELETE FROM kv_store WHERE key = ?
+            ''', (key,))
+            return {"deleted_count": cur.rowcount}
+
+
+    def keys(self, pattern='*'):
+        pattern = pattern.translate(str.maketrans({
+            '\\': '\\\\', '%': '\\%', '_': '\\_', '*': '%', '?': '_'
+        }))
+
+        with self:
+            cur = self.execute('''
+                SELECT key FROM kv_store
+                WHERE key LIKE ? ESCAPE '\\'
+            ''', (pattern,))
+            return [row[0] for row in cur.fetchall()]
+```
+# Usage
+```python
+db = DB()
+
+# 문자열 저장 및 조회
+db['hello'] = 'world'
+print(db['hello'])  # 출력: world (str 타입)
+
+# 숫자 저장 및 조회
+db['number'] = 42
+print(db['number'])  # 출력: 42 (int 타입)
+
+# 바이너리 데이터 저장 및 조회
+db['binary'] = b'binary data'
+print(db['binary'])  # 출력: b'binary data' (bytes 타입)
+
+# 복잡한 객체 저장
+complex_obj = {'name': 'John', 'age': 30, 'city': 'New York'}
+db['complex'] = complex_obj
+loaded_obj = db['complex']
+print(loaded_obj)  # 출력: {'name': 'John', 'age': 30, 'city': 'New York'} (dict 타입)
+```