docs: add Repository.execute examples

Author: vivekpatil017

docs/site/Executing-database-commands.md

@@ -29,6 +29,42 @@ Example use:
 ```ts
 const result = await repository.execute('SELECT * FROM Products');
 ```
+## Examples
+
+### MySQL
+
+Use parameterized queries to avoid SQL injection attacks.
+
+```ts
+const result = await repository.execute(
+  'SELECT * FROM Products WHERE id = ?',
+  [productId]
+);
+```
+
+### PostgreSQL
+
+```ts
+const result = await repository.execute(
+  'SELECT * FROM Products WHERE id = $1',
+  [productId]
+);
+```
+
+### MongoDB
+
+```ts
+const result = await repository.execute(
+  'MyCollection',
+  'aggregate',
+  [
+    {$unwind: '$data'},
+    {$out: 'tempData'},
+  ]
+);
+```
+
+Use parameterized queries whenever possible instead of constructing SQL strings manually.
 
 See API docs for parameter reference, additional information and examples: