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joplin notion extension/Web Development/Go/databases.md

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+databases
+
+sqlite
+https://www.sqlitetutorial.net/sqlite-go/connect/
+
+connecting 
+
+```go
+
+func NewDB() *sql.DB {
+	// err := errors.New("some error")
+
+	db, err := sql.Open("sqlite", "./main.db")
+
+	if err != nil {
+		fmt.Println(err)
+		return nil
+	}
+	fmt.Println("Connected to the SQLite database successfully.")
+
+
+	fmt.Println("Table countries was created successfully.")
+
+	return db
+}
+```
+
+creating table
+```go
+func CreateTable(db *sql.DB) (sql.Result, error) {
+
+	sql := fmt.Sprintf(`CREATE TABLE IF NOT EXISTS  %v(
+        id TEXT PRIMARY KEY,
+        name     TEXT NOT NULL,
+        price REAL NOT NULL,
+        file TEXT 
+    );`, TABLE_NAME)
+
+	return db.Exec(sql)
+
+}
+
+```
+
+findall
+
+```go
+func FindAll(db *sql.DB) ([]types.Book, error) {
+
+	sql := fmt.Sprintf(`select * from %v`, TABLE_NAME)
+
+	rows, err := db.Query(sql)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var books []types.Book
+	for rows.Next() {
+		b := &types.Book{}
+		err := rows.Scan(&b.Id, &b.Name, &b.Price, &b.Filename)
+		if err != nil {
+			return nil, err
+		}
+
+		books = append(books, *b)
+	}
+
+	fmt.Println("finall: ", books)
+
+	return books, nil
+}
+```
+
+we cant just use sql.Rows directly as it is stream so using Next() we read it row by row