Feat(parser): support show create table sql parser. (#150)

* Feat(parser): support show create table sql parser.
Signed-off-by: Zonglei Dong <dongzonglei@apache.org>

* Feat(parser): add show create table sql parser test case.
Signed-off-by: Zonglei Dong <dongzonglei@apache.org>

pisa-proxy/parser/mysql/src/ast/dml.rs

@@ -3103,3 +3103,9 @@ pub struct ShowTableDb {
     pub from_or_in: FromOrIn,
     pub db: String,
 }
+
+#[derive(Debug, Clone)]
+pub struct ShowCreateTable {
+    pub span: Span,
+    pub table: String,
+}

pisa-proxy/parser/mysql/src/ast/mod.rs

@@ -42,6 +42,7 @@ pub enum SqlStmt {
     ShowDatabasesStmt(Box<ShowDatabasesStmt>),
     ShowTablesStmt(Box<ShowTablesStmt>),
     ShowColumnsStmt(Box<ShowColumnsStmt>),
+    ShowCreateTable(Box<ShowCreateTable>),
     Start(Start),
     Commit(Commit),
     Rollback(Rollback),

pisa-proxy/parser/mysql/src/grammar.y

@@ -108,6 +108,7 @@ sql_stmt -> SqlStmt:
   | show_databases_stmt { SqlStmt::ShowDatabasesStmt($1) }
   | show_tables_stmt    { SqlStmt::ShowTablesStmt($1) }
   | show_columns_stmt   { SqlStmt::ShowColumnsStmt($1) }
+  | show_create_table_stmt  { SqlStmt::ShowCreateTable($1) }
   | start               { SqlStmt::Start($1) }
   | create        { SqlStmt::Create($1) }
 
@@ -5977,6 +5978,16 @@ from_or_in -> FromOrIn:
     | 'IN'   { FromOrIn::In }
 ;
 
+show_create_table_stmt -> Box<ShowCreateTable>:
+    'SHOW' 'CREATE' 'TABLE' table_ident
+    {
+        Box::new(ShowCreateTable {
+           span: $span,
+           table: $4,
+        })
+    }
+;
+
 start -> Start:
   START TRANSACTION opt_start_transaction_option_list
   {

pisa-proxy/parser/mysql/src/parser.rs

@@ -128,6 +128,7 @@ mod test {
             "select * from test.test limit 1",
             "select * from test.1test limit 1",
             "SHOW COLUMNS FROM t_order;",
+            "SHOW CREATE TABLE t_order;",
         ];
 
         let p = Parser::new();