Struct Db 

pub struct Db { /* private fields */ }

快捷查询入口（think-orm Db::name() 风格）

不要求定义 Model，仅靠表名 + 方言即可生成 SQL。

Implementations

impl Db

pub fn new(dialect: Box<dyn Dialect>) -> Self

创建快捷查询入口

pub fn name(self, table: impl Into<String>) -> Self

指定表名（等价于 think-orm 的 Db::name('user')）

pub fn select(self, columns: Vec<&str>) -> Self

选择列

pub fn where_cond(self, condition: impl Into<String>) -> Self

WHERE 条件（AND）

pub fn or_where(self, condition: impl Into<String>) -> Self

WHERE 条件（OR）

pub fn where_in(self, field: impl Into<String>, values: Vec<Value>) -> Self

WHERE IN

pub fn where_not_in(self, field: impl Into<String>, values: Vec<Value>) -> Self

WHERE NOT IN

pub fn where_between( self, field: impl Into<String>, start: Value, end: Value, ) -> Self

WHERE BETWEEN

pub fn where_null(self, field: impl Into<String>) -> Self

WHERE IS NULL

pub fn where_not_null(self, field: impl Into<String>) -> Self

WHERE IS NOT NULL

pub fn order_by(self, field: impl Into<String>) -> Self

ORDER BY field ASC

pub fn order_desc(self, field: impl Into<String>) -> Self

ORDER BY field DESC

pub fn group_by(self, field: impl Into<String>) -> Self

GROUP BY

pub fn having(self, condition: impl Into<String>) -> Self

HAVING

pub fn limit(self, limit: usize) -> Self

LIMIT

pub fn offset(self, offset: usize) -> Self

OFFSET

pub fn page(self, page: usize, page_size: usize) -> Self

分页（page 从 1 开始）

pub fn join_inner( self, table: impl Into<String>, on_left: impl Into<String>, on_right: impl Into<String>, ) -> Self

INNER JOIN

pub fn join_left( self, table: impl Into<String>, on_left: impl Into<String>, on_right: impl Into<String>, ) -> Self

LEFT JOIN

pub fn join_right( self, table: impl Into<String>, on_left: impl Into<String>, on_right: impl Into<String>, ) -> Self

RIGHT JOIN

pub fn build_select(&self) -> String

构建 SELECT SQL

pub fn build_insert(&self, data: &HashMap<String, Value>) -> String

构建 INSERT SQL

pub fn build_update(&self, data: &HashMap<String, Value>) -> String

构建 UPDATE SQL

pub fn build_delete(&self) -> String

构建 DELETE SQL

pub fn build_count(&self) -> String

构建 COUNT SQL

pub fn build_exists(&self) -> String

构建 EXISTS SQL

pub fn build_max(&self, field: &str) -> String

构建 MAX SQL

pub fn build_min(&self, field: &str) -> String

构建 MIN SQL

pub fn build_sum(&self, field: &str) -> String

构建 SUM SQL

pub fn build_avg(&self, field: &str) -> String

构建 AVG SQL