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 struct JoinClause {
147    pub table: String,
148    pub alias: Option<String>,
149    pub left_col: String,
150    pub right_col: String,
151}
152
153#[derive(Debug, Clone, PartialEq)]
154pub enum AggFunc {
155    Count,
156    Sum,
157    Avg,
158    Min,
159    Max,
160}
161
162#[derive(Debug, Clone, PartialEq)]
163pub enum SelectExpr {
164    Column(String),
165    Aggregate { func: AggFunc, arg: String, arg_expr: Option<Expr>, alias: Option<String> },
166    Expr { expr: Expr, alias: Option<String> },
167}
168
169impl SelectExpr {
170    pub fn output_name(&self) -> String {
171        match self {
172            SelectExpr::Column(name) => name.clone(),
173            SelectExpr::Aggregate { func, arg, alias, .. } => {
174                if let Some(a) = alias {
175                    a.clone()
176                } else {
177                    let func_name = match func {
178                        AggFunc::Count => "COUNT",
179                        AggFunc::Sum => "SUM",
180                        AggFunc::Avg => "AVG",
181                        AggFunc::Min => "MIN",
182                        AggFunc::Max => "MAX",
183                    };
184                    format!("{}({})", func_name, arg)
185                }
186            }
187            SelectExpr::Expr { expr, alias } => {
188                alias.clone().unwrap_or_else(|| expr.display_name())
189            }
190        }
191    }
192
193    pub fn is_aggregate(&self) -> bool {
194        match self {
195            SelectExpr::Aggregate { .. } => true,
196            SelectExpr::Expr { expr, .. } => expr.contains_aggregate(),
197            _ => false,
198        }
199    }
200}
201
202#[derive(Debug, Clone, PartialEq)]
203pub struct SelectQuery {
204    pub columns: ColumnList,
205    pub table: String,
206    pub table_alias: Option<String>,
207    pub subquery: Option<Box<SelectQuery>>,
208    pub joins: Vec<JoinClause>,
209    pub where_clause: Option<WhereClause>,
210    pub group_by: Option<Vec<String>>,
211    pub having: Option<WhereClause>,
212    pub order_by: Option<Vec<OrderSpec>>,
213    pub limit: Option<i64>,
214}
215
216#[derive(Debug, Clone, PartialEq)]
217pub enum ColumnList {
218    All,
219    Named(Vec<SelectExpr>),
220}
221
222#[derive(Debug, Clone, PartialEq)]
223pub struct InsertQuery {
224    pub table: String,
225    pub columns: Vec<String>,
226    pub values: Vec<SqlValue>,
227}
228
229#[derive(Debug, Clone, PartialEq)]
230pub struct UpdateQuery {
231    pub table: String,
232    pub assignments: Vec<(String, SqlValue)>,
233    pub where_clause: Option<WhereClause>,
234}
235
236#[derive(Debug, Clone, PartialEq)]
237pub struct DeleteQuery {
238    pub table: String,
239    pub where_clause: Option<WhereClause>,
240}
241
242#[derive(Debug, Clone, PartialEq)]
243pub struct AlterRenameFieldQuery {
244    pub table: String,
245    pub old_name: String,
246    pub new_name: String,
247}
248
249#[derive(Debug, Clone, PartialEq)]
250pub struct AlterDropFieldQuery {
251    pub table: String,
252    pub field_name: String,
253}
254
255#[derive(Debug, Clone, PartialEq)]
256pub struct AlterMergeFieldsQuery {
257    pub table: String,
258    pub sources: Vec<String>,
259    pub into: String,
260}
261
262#[derive(Debug, Clone, PartialEq)]
263pub struct CreateViewQuery {
264    pub view_name: String,
265    pub columns: Option<Vec<String>>,
266    pub query: Box<SelectQuery>,
267}
268
269#[derive(Debug, Clone, PartialEq)]
270pub struct DropViewQuery {
271    pub view_name: String,
272}
273
274#[derive(Debug, Clone, PartialEq)]
275pub enum Statement {
276    Select(SelectQuery),
277    Insert(InsertQuery),
278    Update(UpdateQuery),
279    Delete(DeleteQuery),
280    AlterRename(AlterRenameFieldQuery),
281    AlterDrop(AlterDropFieldQuery),
282    AlterMerge(AlterMergeFieldsQuery),
283    CreateView(CreateViewQuery),
284    DropView(DropViewQuery),
285}
286
287impl Statement {
288    pub fn table_name(&self) -> &str {
289        match self {
290            Statement::Select(q) => &q.table,
291            Statement::Insert(q) => &q.table,
292            Statement::Update(q) => &q.table,
293            Statement::Delete(q) => &q.table,
294            Statement::AlterRename(q) => &q.table,
295            Statement::AlterDrop(q) => &q.table,
296            Statement::AlterMerge(q) => &q.table,
297            Statement::CreateView(q) => &q.view_name,
298            Statement::DropView(q) => &q.view_name,
299        }
300    }
301}
mdql_core/query_ast.rs

mdql_core/
query_ast.rs
