Struct QueryBuilder 

pub struct QueryBuilder { /* private fields */ }

查询构建器

Implementations

impl QueryBuilder

pub fn new(table: String, engine: Arc<RwLock<MemoryEngine>>) -> Self

pub fn eq(self, field: &str, value: DbValue) -> Self

pub fn ne(self, field: &str, value: DbValue) -> Self

pub fn lt(self, field: &str, value: DbValue) -> Self

pub fn le(self, field: &str, value: DbValue) -> Self

pub fn gt(self, field: &str, value: DbValue) -> Self

pub fn ge(self, field: &str, value: DbValue) -> Self

pub fn in_list(self, field: &str, values: Vec<DbValue>) -> Self

pub fn contains(self, field: &str, value: &str) -> Self

pub fn and(self, other: QueryBuilder) -> Self

pub fn order_by(self, field: &str, order: Order) -> Self

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

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

pub fn inner_join( self, right_table: &str, left_field: &str, right_field: &str, ) -> Self

pub fn left_join( self, right_table: &str, left_field: &str, right_field: &str, ) -> Self

pub fn right_join( self, right_table: &str, left_field: &str, right_field: &str, ) -> Self

pub fn full_join( self, right_table: &str, left_field: &str, right_field: &str, ) -> Self

pub fn select(self, columns: &[&str]) -> Self

pub fn count(self) -> Self

COUNT(*) - 统计行数

pub fn count_column(self, column: &str) -> Self

COUNT(column) - 统计非 NULL 行数

pub fn sum(self, column: &str) -> Self

SUM(column) - 求和

pub fn avg(self, column: &str) -> Self

AVG(column) - 平均值

pub fn max(self, column: &str) -> Self

MAX(column) - 最大值

pub fn min(self, column: &str) -> Self

MIN(column) - 最小值

pub fn alias(self, name: &str) -> Self

设置聚合结果别名

pub fn group_by(self, columns: &[&str]) -> Self

GROUP BY 子句

pub fn having_eq(self, value: DbValue) -> Self

HAVING 子句 - 等于

pub fn having_ne(self, value: DbValue) -> Self

HAVING 子句 - 不等于

pub fn having_gt(self, value: DbValue) -> Self

HAVING 子句 - 大于

pub fn having_ge(self, value: DbValue) -> Self

HAVING 子句 - 大于等于

pub fn having_lt(self, value: DbValue) -> Self

HAVING 子句 - 小于

pub fn having_le(self, value: DbValue) -> Self

HAVING 子句 - 小于等于

pub fn execute(self) -> DbResult<Vec<Row>>

执行查询