ormer 0.1.13

A minimalist ORM framework that supports SQLite, PostgreSQL, MySQL, and SqlServer
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98

/// 过滤表达式
#[derive(Debug, Clone)]
pub enum FilterExpr {
    /// 简单比较:column operator value
    Comparison {
        column: String,
        operator: String,
        value: Value,
    },
    /// 列-列比较:column1 operator column2
    ColumnComparison {
        left_column: String,
        operator: String,
        right_column: String,
    },
    /// IN 语句:column IN (value1, value2, ...)
    In { column: String, values: Vec<Value> },
    /// 子查询 IN: column IN (subquery)
    InSubquery {
        column: String,
        subquery_sql: String,
        subquery_params: Vec<crate::model::Value>,
    },
    /// AND 连接
    And(Box<FilterExpr>, Box<FilterExpr>),
    /// OR 连接
    Or(Box<FilterExpr>, Box<FilterExpr>),
}

/// 值类型（用于过滤）
#[derive(Debug, Clone)]
pub enum Value {
    Integer(i64),
    BigInt(i128),
    Text(String),
    Real(f64),
    Boolean(bool),
    Bytes(Vec<u8>),
    DateTime(chrono::DateTime<chrono::Utc>),
    Json(serde_json::Value),
    Uuid(uuid::Uuid),
    Null,
}

/// 子查询 trait - 用于 is_in 方法
pub trait Subquery {
    /// 获取子查询的 SQL 和参数
    fn to_subquery_sql(&self) -> (String, Vec<crate::model::Value>);
}

impl FilterExpr {
    pub fn and(self, other: FilterExpr) -> Self {
        FilterExpr::And(Box::new(self), Box::new(other))
    }

    pub fn or(self, other: FilterExpr) -> Self {
        FilterExpr::Or(Box::new(self), Box::new(other))
    }
}

/// 排序方向
#[derive(Debug, Clone)]
pub enum OrderDirection {
    Asc,
    Desc,
}

/// 排序表达式
#[derive(Debug, Clone)]
pub struct OrderBy {
    pub column: String,
    pub direction: OrderDirection,
}

impl OrderBy {
    pub fn asc(column: String) -> Self {
        Self {
            column,
            direction: OrderDirection::Asc,
        }
    }

    pub fn desc(column: String) -> Self {
        Self {
            column,
            direction: OrderDirection::Desc,
        }
    }

    /// 将 OrderBy 转换为 SQL 字符串
    pub fn to_sql(&self) -> String {
        let dir = match self.direction {
            OrderDirection::Asc => "ASC",
            OrderDirection::Desc => "DESC",
        };
        format!("{} {}", self.column, dir)
    }
}