feat(ast): support EXPLAIN VERBOSE alias (#16161) (#19726)

Author: KKould

src/query/ast/src/parser/statement.rs

@@ -79,9 +79,19 @@ fn query_statement(i: Input) -> IResult<Statement> {
 }
 
 pub fn statement_body(i: Input) -> IResult<Statement> {
+    let explain_options = map(
+        rule! {
+            "(" ~ #comma_separated_list1(explain_option) ~ ")"
+        },
+        |(a, opts, b)| (merge_span(Some(a.span), Some(b.span)), opts),
+    );
+    let explain_verbose_alias = map(rule! { VERBOSE }, |verbose| {
+        (Some(verbose.span), vec![ExplainOption::Verbose])
+    });
+
     let explain = map_res(
         rule! {
-            EXPLAIN ~ ( "(" ~ #comma_separated_list1(explain_option) ~ ")" )? ~ ( AST | SYNTAX | PIPELINE | JOIN | GRAPH | FRAGMENTS | RAW | OPTIMIZED | MEMO | DECORRELATED | PERF)? ~ #statement
+            EXPLAIN ~ ( #explain_options | #explain_verbose_alias )? ~ ( AST | SYNTAX | PIPELINE | JOIN | GRAPH | FRAGMENTS | RAW | OPTIMIZED | MEMO | DECORRELATED | PERF)? ~ #statement
         },
         |(_, options, opt_kind, statement)| {
             Ok(Statement::Explain {
@@ -105,9 +115,7 @@ pub fn statement_body(i: Input) -> IResult<Statement> {
                     None => ExplainKind::Plan,
                     _ => unreachable!(),
                 },
-                options: options
-                    .map(|(a, opts, b)| (merge_span(Some(a.span), Some(b.span)), opts))
-                    .unwrap_or_default(),
+                options: options.unwrap_or_default(),
                 query: Box::new(statement.stmt),
             })
         },
@@ -2783,7 +2791,7 @@ pub fn statement_body(i: Input) -> IResult<Statement> {
         HintPrefix | LParen | FROM => query_statement(i),
         EXPLAIN => rule!(
             #explain_perf : "`EXPLAIN PERF [(events='<event>,...')] <statement>`"
-            | #explain : "`EXPLAIN [PIPELINE | GRAPH] <statement>`"
+            | #explain : "`EXPLAIN [VERBOSE | (<option>, ...)] [PIPELINE | GRAPH] <statement>`"
             | #explain_analyze : "`EXPLAIN ANALYZE <statement>`"
         ).parse(i),
         REPORT => rule!(#report: "`REPORT ISSUE <statement>`").parse(i),

src/query/ast/tests/it/display.rs

@@ -12,6 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use databend_common_ast::ast::ExplainKind;
+use databend_common_ast::ast::ExplainOption;
+use databend_common_ast::ast::Statement;
 use databend_common_ast::parser::Dialect;
 use databend_common_ast::parser::parse_sql;
 use databend_common_ast::parser::tokenize_sql;
@@ -82,3 +85,24 @@ fn test_parse_sql_nested_join_conditions_without_panic() {
         parse_sql(&tokens, Dialect::PostgreSQL).unwrap();
     }
 }
+
+#[test]
+fn test_explain_verbose_alias_display() {
+    let tokens = tokenize_sql("EXPLAIN VERBOSE SELECT * FROM t").unwrap();
+    let (stmt, _) = parse_sql(&tokens, Dialect::PostgreSQL).unwrap();
+
+    match &stmt {
+        Statement::Explain {
+            kind,
+            options: (_, options),
+            ..
+        } => {
+            assert_eq!(kind, &ExplainKind::Plan);
+            assert_eq!(options, &vec![ExplainOption::Verbose]);
+        }
+        _ => panic!("expected EXPLAIN statement"),
+    }
+
+    assert_eq!(stmt.to_string(), "EXPLAIN(VERBOSE) SELECT * FROM t");
+    test_stmt_display("EXPLAIN VERBOSE SELECT * FROM t");
+}

tests/sqllogictests/suites/mode/standalone/explain/explain.test

@@ -37,6 +37,34 @@ TableScan
 ├── push downs: [filters: [t1.a (#0) > 0], limit: NONE]
 └── estimated rows: 0.00
 
+query T
+explain(verbose) select * from numbers(0)
+----
+TableScan
+├── table: default.system.numbers
+├── scan id: 0
+├── output columns: [number (#0)]
+├── read rows: 0
+├── read size: 0
+├── partitions total: 1
+├── partitions scanned: 1
+├── push downs: [filters: [], limit: NONE]
+└── estimated rows: 0.00
+
+query T
+explain verbose select * from numbers(0)
+----
+TableScan
+├── table: default.system.numbers
+├── scan id: 0
+├── output columns: [number (#0)]
+├── read rows: 0
+├── read size: 0
+├── partitions total: 1
+├── partitions scanned: 1
+├── push downs: [filters: [], limit: NONE]
+└── estimated rows: 0.00
+
 query T
 explain select * from t1, t2 where (t1.a = t2.a and t1.a > 3) or (t1.a = t2.a and t2.a > 5 and t1.a > 1)
 ----