docs: update docs

Author: suyuan32

src/en/guide/interview/golang/basic/1-basic.md

@@ -220,6 +220,72 @@ s := []string{"red", "black"}
 ```
 :::
 
+## Map
+
+### Can an uninitialized Map read a key?
+
+::: details Answer
+
+Yes, an uninitialized `map` that hasn't undergone `make` initialization will return the zero value of the current type for any `key` read.
+
+```go
+package main
+
+import "fmt"
+
+func main() {
+	var m map[int]int
+
+	fmt.Println(m[1])
+}
+
+// Output:
+// 0
+```
+:::
+
+### What happens if you assign a value to an uninitialized Map?
+
+::: details Answer
+
+It will trigger a `panic` exception error.
+
+```go
+package main
+
+func main() {
+	var m map[int]int
+
+	m[1] = 1
+}
+
+// Output:
+// panic: assignment to entry in nil map
+```
+
+:::
+
+### What happens if you delete a key from an uninitialized Map?
+
+::: details Answer
+
+In earlier versions, performing a `delete` operation on an uninitialized `map` would throw a `panic` error. In current versions, performing a `delete` operation on an uninitialized `map` will not cause an error.
+
+```go
+package main
+
+func main() {
+	var m map[int]int
+
+	delete(m, 1)
+}
+
+// Output:
+// 
+```
+
+:::
+
 
 ## Others
 ### What is the difference between `rune` and `byte` in Go?
@@ -491,69 +557,36 @@ The advantage of using pointer transfer is that it directly transfers the addres
 
 :::
 
+### Golang Common String Concatenation Methods and Their Efficiency
 
-## Map
-
-### Can an uninitialized Map read a key?
-
-::: details Answer
-
-Yes, an uninitialized `map` that hasn't undergone `make` initialization will return the zero value of the current type for any `key` read.
-
-```go
-package main
-
-import "fmt"
-
-func main() {
-	var m map[int]int
-
-	fmt.Println(m[1])
-}
-
-// Output:
-// 0
-```
-:::
-
-### What happens if you assign a value to an uninitialized Map?
-
-::: details Answer
+::: details
 
-It will trigger a `panic` exception error.
+| Method            | Description                                                                                                                       |
+| ----------------- | --------------------------------------------------------------------------------------------------------------------------------- |
+| `+`               | Using the `+` operator for concatenation involves iterating over the strings, calculating, and allocating new space.              |
+| `fmt.Sprintf`     | Since `printf` allows format specifiers like `%d`, `sprintf` uses reflection to convert different types, which is less efficient. |
+| `strings.Builder` | Concatenation using `WriteString()` internally uses `[]byte` slices and `unsafe.pointer` pointers.                                |
+| `bytes.Buffer`    | A byte buffer, underlyingly based on `[]byte` slices.                                                                             |
+| `strings.Join`    | `strings.Join` is implemented based on `strings.Builder`, preallocating memory space with `b.Grow(n)`, making it more efficient.  |
 
-```go
-package main
+> [!important]
+> What's the difference between `strings.Builder` and `bytes.Buffer`?
+> 1. `strings.Builder` preallocates space, reducing reallocations and improving efficiency, suitable for longer string concatenations.
+> 2. `bytes.Buffer` is mainly used for handling individual bytes, offering operations like deletion and replacement that `strings.Builder` lacks.
 
-func main() {
-	var m map[int]int
-
-	m[1] = 1
-}
-
-// Output:
-// panic: assignment to entry in nil map
-```
+> [!tip]
+> Efficiency ranking:
+> `strings.Join` ≈ `strings.Builder` > `bytes.Buffer` > `+` > `fmt.Sprintf`
 
 :::
 
-### What happens if you delete a key from an uninitialized Map?
-
-::: details Answer
-
-In earlier versions, performing a `delete` operation on an uninitialized `map` would throw a `panic` error. In current versions, performing a `delete` operation on an uninitialized `map` will not cause an error.
+### What Are Tags Used for in Golang?
 
-```go
-package main
+::: details
 
-func main() {
-	var m map[int]int
-
-	delete(m, 1)
-}
-
-// Output:
-// 
-```
+In Go, struct fields can have various custom tags. When parsing a struct, these tags can be extracted for convenient operations. Common tags include:
 
-:::
+- `json`: Used to declare JSON serialization and deserialization operations, specifying fields and options.
+- `db`: Primarily used for database field configuration, often in libraries like sqlx.
+- `form`: Commonly used in web frameworks to declare form field bindings.
+- `validate`: Frequently used for field validation rules by validators.

src/guide/interview/golang/basic/1-basic.md

@@ -275,6 +275,72 @@ s := []string{"red", "black"}
 ```
 :::
 
+## Map
+
+### 未初始化的 Map 可以读取 key 吗？
+
+::: details 答案
+
+可以的，未执行 `make` 初始化的 `map` 读取任何 `key` 都会返回当前类型的空值
+
+```go
+package main
+
+import "fmt"
+
+func main() {
+	var m map[int]int
+
+	fmt.Println(m[1])
+}
+
+// 结果：
+// 0
+```
+:::
+
+### 如果对未初始化的 Map 赋值会怎么样？
+
+::: details 答案
+
+会触发 `panic` 异常错误
+
+```go
+package main
+
+func main() {
+	var m map[int]int
+
+	m[1] = 1
+}
+
+// 结果：
+// panic: assignment to entry in nil map
+```
+
+:::
+
+### 如果对未初始化的 Map 进行删除 key 的操作会发生什么？
+
+::: details 答案
+
+早期如果对未初始化的 `map` 进行 `delete` 操作会报 `panic` 错误， 现在的版本对于未初始化的 `map` 进行 `delete` 是不会报错的。
+
+```go
+package main
+
+func main() {
+	var m map[int]int
+
+	delete(m, 1)
+}
+
+// 结果：
+// 
+```
+
+:::
+
 
 ## 其他
 ###   Go 中的 `rune` 和 `byte` 有什么区别？
@@ -549,68 +615,38 @@ func main() {
 
 :::
 
-## Map
+### Golang 常见的字符串拼接方式有哪些？效率有何不同？
 
-### 未初始化的 Map 可以读取 key 吗？
-
-::: details 答案
-
-可以的，未执行 `make` 初始化的 `map` 读取任何 `key` 都会返回当前类型的空值
-
-```go
-package main
+::: details
 
-import "fmt"
+| 方法              | 描述                                                                                                                   |
+| ----------------- | ---------------------------------------------------------------------------------------------------------------------- |
+| `+`               | 使用 `+` 操作符进行拼接会对遍历字符串，计算并开辟一个新的空间来存储合并后的字符串                                      |
+| `fmt.Sprintf`     | 由于 `printf` 中可以使用 `%d` 等表示变量类型， `sprintf` 需要使用到反射来将不同的类型进行转换，效率较低                |
+| `strings.Builder` | 使用 `WriteString()` 进行拼接操作，内部使用 `[]byte` 切片和 `unsafe.pointer` 指针实现                                  |
+| `bytes.Buffer`    | `byte` 缓冲器，底层是 `[]byte` 切片                                                                                    |
+| `strings.Join`    | `strings.Join` 是基于 `strings.Builder` 来实现的，在 `Join` 方法内调用了 `b.Grow(n)` 方法， 预分配了内存空间，较为高效 |
 
-func main() {
-	var m map[int]int
+> [!important]
+> `strings.Builder` 和 `bytes.Buffer` 有什么区别？
+> 1. `strings.Builder` 会预分配空间，减少扩容，效率更高，适合较长的字符串拼接操作
+> 2. `bytes.Buffer` 主要用于处理单个字符，拥有许多针对单个 `byte` 的操作，如删除替换等，这个是 `strings.Builder` 没有的。
 
-	fmt.Println(m[1])
-}
+> [!tip]
+> 效率排行
+> strings.Join ≈ strings.Builder > bytes.Buffer > "+" > fmt.Sprintf
 
-// 结果：
-// 0
-```
 :::
 
-### 如果对未初始化的 Map 赋值会怎么样？
+### Golang 中的 Tag 有什么用？
 
-::: details 答案
+::: details
 
-会触发 `panic` 异常错误
+Golang 的结构体字段可以添加各类自定义的 `Tag`, 在解析结构体时可以使用函数将 `Tag` 解析出来，方便进行操作，常见的 `Tag`:
 
-```go
-package main
-
-func main() {
-	var m map[int]int
-
-	m[1] = 1
-}
-
-// 结果：
-// panic: assignment to entry in nil map
-```
-
-:::
-
-### 如果对未初始化的 Map 进行删除 key 的操作会发生什么？
-
-::: details 答案
-
-早期如果对未初始化的 `map` 进行 `delete` 操作会报 `panic` 错误， 现在的版本对于未初始化的 `map` 进行 `delete` 是不会报错的。
-
-```go
-package main
-
-func main() {
-	var m map[int]int
-
-	delete(m, 1)
-}
-
-// 结果：
-// 
-```
+- json: json tag 主要用于声明 json 在序列化和反序列化时的操作，如字段，可选等功能
+- db: 主要用于声明数据库字段配置，用在 sqlx 中
+- form: 常用在 web 框架中用于声明接收表单字段
+- validate: 常用于校验器对于字段校验的配置
 
 :::