mdql_core/
query_ast.rs

1//! AST types for the MDQL SQL subset.
2
3// ── AST nodes ──────────────────────────────────────────────────────────────
4
5#[derive(Debug, Clone, PartialEq)]
6pub enum ArithOp {
7    Add,
8    Sub,
9    Mul,
10    Div,
11    Mod,
12}
13
14#[derive(Debug, Clone, PartialEq)]
15pub enum Expr {
16    Literal(SqlValue),
17    Column(String),
18    BinaryOp { left: Box<Expr>, op: ArithOp, right: Box<Expr> },
19    UnaryMinus(Box<Expr>),
20    Case { whens: Vec<(WhereClause, Box<Expr>)>, else_expr: Option<Box<Expr>> },
21    DateAdd { date: Box<Expr>, days: Box<Expr> },
22    DateDiff { left: Box<Expr>, right: Box<Expr> },
23    CurrentDate,
24    CurrentTimestamp,
25    Aggregate { func: AggFunc, arg: String, arg_expr: Option<Box<Expr>> },
26}
27
28impl Expr {
29    pub fn as_column(&self) -> Option<&str> {
30        if let Expr::Column(name) = self { Some(name) } else { None }
31    }
32
33    pub fn display_name(&self) -> String {
34        match self {
35            Expr::Literal(SqlValue::Int(n)) => n.to_string(),
36            Expr::Literal(SqlValue::Float(f)) => f.to_string(),
37            Expr::Literal(SqlValue::String(s)) => format!("'{}'", s),
38            Expr::Literal(SqlValue::Null) => "NULL".to_string(),
39            Expr::Literal(SqlValue::List(_)) => "list".to_string(),
40            Expr::Column(name) => name.clone(),
41            Expr::BinaryOp { left, op, right } => {
42                let op_str = match op {
43                    ArithOp::Add => "+",
44                    ArithOp::Sub => "-",
45                    ArithOp::Mul => "*",
46                    ArithOp::Div => "/",
47                    ArithOp::Mod => "%",
48                };
49                format!("{} {} {}", left.display_name(), op_str, right.display_name())
50            }
51            Expr::UnaryMinus(inner) => format!("-{}", inner.display_name()),
52            Expr::Case { .. } => "CASE".to_string(),
53            Expr::DateAdd { date, days } => format!("DATE_ADD({}, {})", date.display_name(), days.display_name()),
54            Expr::DateDiff { left, right } => format!("DATEDIFF({}, {})", left.display_name(), right.display_name()),
55            Expr::CurrentDate => "CURRENT_DATE".to_string(),
56            Expr::CurrentTimestamp => "CURRENT_TIMESTAMP".to_string(),
57            Expr::Aggregate { func, arg, .. } => {
58                let func_name = match func {
59                    AggFunc::Count => "COUNT",
60                    AggFunc::Sum => "SUM",
61                    AggFunc::Avg => "AVG",
62                    AggFunc::Min => "MIN",
63                    AggFunc::Max => "MAX",
64                };
65                format!("{}({})", func_name, arg)
66            }
67        }
68    }
69
70    pub fn contains_aggregate(&self) -> bool {
71        match self {
72            Expr::Aggregate { .. } => true,
73            Expr::BinaryOp { left, right, .. } => {
74                left.contains_aggregate() || right.contains_aggregate()
75            }
76            Expr::UnaryMinus(inner) => inner.contains_aggregate(),
77            Expr::Case { whens, else_expr } => {
78                whens.iter().any(|(_, e)| e.contains_aggregate())
79                    || else_expr.as_ref().map_or(false, |e| e.contains_aggregate())
80            }
81            _ => false,
82        }
83    }
84}
85
86#[derive(Debug, Clone, PartialEq)]
87pub struct OrderSpec {
88    pub column: String,
89    pub expr: Option<Expr>,
90    pub descending: bool,
91}
92
93#[derive(Debug, Clone, PartialEq)]
94pub enum CmpOp {
95    Eq,
96    Ne,
97    Lt,
98    Gt,
99    Le,
100    Ge,
101    Like,
102    NotLike,
103    In,
104    IsNull,
105    IsNotNull,
106}
107
108#[derive(Debug, Clone, PartialEq)]
109pub enum BoolOpKind {
110    And,
111    Or,
112}
113
114#[derive(Debug, Clone, PartialEq)]
115pub struct Comparison {
116    pub column: String,
117    pub op: CmpOp,
118    pub value: Option<SqlValue>,
119    pub left_expr: Option<Expr>,
120    pub right_expr: Option<Expr>,
121}
122
123#[derive(Debug, Clone, PartialEq)]
124pub struct BoolOp {
125    pub op: BoolOpKind,
126    pub left: Box<WhereClause>,
127    pub right: Box<WhereClause>,
128}
129
130#[derive(Debug, Clone, PartialEq)]
131pub enum WhereClause {
132    Comparison(Comparison),
133    BoolOp(BoolOp),
134}
135
136#[derive(Debug, Clone, PartialEq)]
137pub enum SqlValue {
138    String(String),
139    Int(i64),
140    Float(f64),
141    Null,
142    List(Vec<SqlValue>),
143}
144
145#[derive(Debug, Clone, PartialEq)]
146pub enum JoinType {
147    Inner,
148    Left,
149}
150
151#[derive(Debug, Clone, PartialEq)]
152pub struct JoinClause {
153    pub join_type: JoinType,
154    pub table: String,
155    pub alias: Option<String>,
156    pub left_col: String,
157    pub right_col: String,
158}
159
160#[derive(Debug, Clone, PartialEq)]
161pub enum AggFunc {
162    Count,
163    Sum,
164    Avg,
165    Min,
166    Max,
167}
168
169#[derive(Debug, Clone, PartialEq)]
170pub enum SelectExpr {
171    Column(String),
172    Aggregate { func: AggFunc, arg: String, arg_expr: Option<Expr>, alias: Option<String> },
173    Expr { expr: Expr, alias: Option<String> },
174}
175
176impl SelectExpr {
177    pub fn output_name(&self) -> String {
178        match self {
179            SelectExpr::Column(name) => name.clone(),
180            SelectExpr::Aggregate { func, arg, alias, .. } => {
181                if let Some(a) = alias {
182                    a.clone()
183                } else {
184                    let func_name = match func {
185                        AggFunc::Count => "COUNT",
186                        AggFunc::Sum => "SUM",
187                        AggFunc::Avg => "AVG",
188                        AggFunc::Min => "MIN",
189                        AggFunc::Max => "MAX",
190                    };
191                    format!("{}({})", func_name, arg)
192                }
193            }
194            SelectExpr::Expr { expr, alias } => {
195                alias.clone().unwrap_or_else(|| expr.display_name())
196            }
197        }
198    }
199
200    pub fn is_aggregate(&self) -> bool {
201        match self {
202            SelectExpr::Aggregate { .. } => true,
203            SelectExpr::Expr { expr, .. } => expr.contains_aggregate(),
204            _ => false,
205        }
206    }
207}
208
209#[derive(Debug, Clone, PartialEq)]
210pub struct SelectQuery {
211    pub columns: ColumnList,
212    pub table: String,
213    pub table_alias: Option<String>,
214    pub subquery: Option<Box<SelectQuery>>,
215    pub joins: Vec<JoinClause>,
216    pub where_clause: Option<WhereClause>,
217    pub group_by: Option<Vec<String>>,
218    pub having: Option<WhereClause>,
219    pub order_by: Option<Vec<OrderSpec>>,
220    pub limit: Option<i64>,
221}
222
223#[derive(Debug, Clone, PartialEq)]
224pub enum ColumnList {
225    All,
226    Named(Vec<SelectExpr>),
227}
228
229#[derive(Debug, Clone, PartialEq)]
230pub struct InsertQuery {
231    pub table: String,
232    pub columns: Vec<String>,
233    pub values: Vec<SqlValue>,
234}
235
236#[derive(Debug, Clone, PartialEq)]
237pub struct UpdateQuery {
238    pub table: String,
239    pub assignments: Vec<(String, SqlValue)>,
240    pub where_clause: Option<WhereClause>,
241}
242
243#[derive(Debug, Clone, PartialEq)]
244pub struct DeleteQuery {
245    pub table: String,
246    pub where_clause: Option<WhereClause>,
247}
248
249#[derive(Debug, Clone, PartialEq)]
250pub struct AlterRenameFieldQuery {
251    pub table: String,
252    pub old_name: String,
253    pub new_name: String,
254}
255
256#[derive(Debug, Clone, PartialEq)]
257pub struct AlterDropFieldQuery {
258    pub table: String,
259    pub field_name: String,
260}
261
262#[derive(Debug, Clone, PartialEq)]
263pub struct AlterMergeFieldsQuery {
264    pub table: String,
265    pub sources: Vec<String>,
266    pub into: String,
267}
268
269#[derive(Debug, Clone, PartialEq)]
270pub struct CreateViewQuery {
271    pub view_name: String,
272    pub columns: Option<Vec<String>>,
273    pub query: Box<SelectQuery>,
274}
275
276#[derive(Debug, Clone, PartialEq)]
277pub struct DropViewQuery {
278    pub view_name: String,
279}
280
281#[derive(Debug, Clone, PartialEq)]
282pub enum Statement {
283    Select(SelectQuery),
284    Insert(InsertQuery),
285    Update(UpdateQuery),
286    Delete(DeleteQuery),
287    AlterRename(AlterRenameFieldQuery),
288    AlterDrop(AlterDropFieldQuery),
289    AlterMerge(AlterMergeFieldsQuery),
290    CreateView(CreateViewQuery),
291    DropView(DropViewQuery),
292}
293
294impl Statement {
295    pub fn table_name(&self) -> &str {
296        match self {
297            Statement::Select(q) => &q.table,
298            Statement::Insert(q) => &q.table,
299            Statement::Update(q) => &q.table,
300            Statement::Delete(q) => &q.table,
301            Statement::AlterRename(q) => &q.table,
302            Statement::AlterDrop(q) => &q.table,
303            Statement::AlterMerge(q) => &q.table,
304            Statement::CreateView(q) => &q.view_name,
305            Statement::DropView(q) => &q.view_name,
306        }
307    }
308}
mdql_core/query_ast.rs

mdql_core/
query_ast.rs
