qstommyshu commented on code in PR #15736:
URL: https://github.com/apache/datafusion/pull/15736#discussion_r2047992548
##########
datafusion/sql/src/parser.rs:
##########
@@ -469,9 +473,101 @@ impl<'a> DFParser<'a> {
}
_ => {
// use sqlparser-rs parser
- Ok(Statement::Statement(Box::from(
- self.parser.parse_statement()?,
- )))
+ let mut stmt = self.parser.parse_statement()?;
+
+ use sqlparser::ast::{DataType, Expr, Spanned, Value};
+
+ if let sqlparser::ast::Statement::Query(query) = &mut
stmt {
+ if let sqlparser::ast::SetExpr::Select(select) =
+ &mut *query.body
+ {
+ // if missing from
+ if select.from.is_empty() {
+ let mut new_projection = Vec::new();
+
+ for expr in &select.projection {
+ match expr {
+
sqlparser::ast::SelectItem::UnnamedExpr(
+ cast_expr,
+ ) => {
+ if let Expr::Cast {
+ expr: inner_expr,
+ data_type,
+ ..
+ } = cast_expr
+ {
+ let inner_str = match
&**inner_expr {
+
Expr::Value(sqlparser::ast::ValueWithSpan { value:
Value::SingleQuotedString(s), .. }) => {
+
format!("'{}'", s)
+ },
+
Expr::Value(sqlparser::ast::ValueWithSpan { value: Value::Number(n, _), .. })
=> {
+ n.clone()
+ },
+ // TODO: need to
take care of other types of values, like TimeStamp, etc...
+ _ =>
format!("{:?}", inner_expr),
+ };
+
+ // get cast to type string
+ let type_str = match
data_type {
+ DataType::Int(_) =>
"INT",
+ DataType::BigInt(_) =>
"BIGINT",
+ DataType::SmallInt(_)
=> {
+ "SMALLINT"
+ }
+ DataType::Boolean =>
"BOOLEAN",
+ DataType::Varchar(_)
=> "VARCHAR",
+ DataType::Float(_) =>
"FLOAT",
+ DataType::Double(_) =>
"DOUBLE",
+ DataType::Text =>
"TEXT",
+ // TODO: need to
support more DataType, probably use an Extension Trait
Review Comment:
Currently, supported data type result would look like this:
`select cast('1' as int);`
```
+------------------+
| cast('1' as int) |
+------------------+
| 1 |
+------------------+
```
unsupported data type result would look like this:
`select cast(1 as string);`
```
+-------------------------+
| cast(1 as string(none)) |
+-------------------------+
| 1 |
+-------------------------+
```
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
