fix: call before_first for call next

app/embedded/execquery.rs

@@ -63,6 +63,7 @@ fn print_result_set(mut results: EmbeddedResultSet) -> Result<i32> {
     println!();
     // scan record
     let mut c = 0;
+    results.before_first()?;
     while results.next() {
         c += 1;
         print_record(&mut results, &meta)?;

app/network/execquery.rs

@@ -69,6 +69,7 @@ async fn print_result_set(mut results: NetworkResultSet) -> Result<(i32, i32)> {
     println!();
     // scan record
     let mut total_count = 0;
+    results.before_first().expect("before first");
     loop {
         let rows = results.get_rows(MAX_ROWS, &meta).await.expect("get rows");
         let c = rows.len();

capnp/remote.capnp

@@ -216,16 +216,17 @@ interface DateBox {
 interface RemoteResultSet {
   # result set
 
-  next        @0 () -> (val :BoolBox);
-  close       @1 () -> (res :TxBox);
-  getMetadata @2 () -> (metadata :RemoteMetaData);
-  getInt16    @3 (fldname :Text) -> (val :Int16Box);
-  getInt32    @4 (fldname :Text) -> (val :Int32Box);
-  getString   @5 (fldname :Text) -> (val :StringBox);
-  getBool     @6 (fldname :Text) -> (val :BoolBox);
-  getDate     @7 (fldname :Text) -> (val :DateBox);
-  getRow      @8 () -> (row :Row); # get one record
-  getRows     @9 (limit :UInt32) -> (count :UInt32, rows :List(Row)); # get records up to limit
+  beforeFirst @0 () -> (val :BoolBox);
+  next        @1 () -> (val :BoolBox);
+  close       @2 () -> (res :TxBox);
+  getMetadata @3 () -> (metadata :RemoteMetaData);
+  getInt16    @4 (fldname :Text) -> (val :Int16Box);
+  getInt32    @5 (fldname :Text) -> (val :Int32Box);
+  getString   @6 (fldname :Text) -> (val :StringBox);
+  getBool     @7 (fldname :Text) -> (val :BoolBox);
+  getDate     @8 (fldname :Text) -> (val :DateBox);
+  getRow      @9 () -> (row :Row); # get one record
+  getRows     @10 (limit :UInt32) -> (count :UInt32, rows :List(Row)); # get records up to limit
 
   struct Row {
     # record

src/rdbc/embedded/resultset.rs

@@ -32,6 +32,7 @@ impl<'a> EmbeddedResultSet<'a> {
 
 impl<'a> ResultSetAdapter for EmbeddedResultSet<'a> {
     type Meta = EmbeddedMetaData;
+    type Setuped = ();
     type Next = bool;
     type Int16Value = i16;
     type Int32Value = i32;
@@ -40,6 +41,9 @@ impl<'a> ResultSetAdapter for EmbeddedResultSet<'a> {
     type DateValue = NaiveDate;
     type Res = ();
 
+    fn before_first(&self) -> Result<Self::Setuped> {
+        self.s.lock().unwrap().before_first()
+    }
     fn next(&self) -> Self::Next {
         self.s.lock().unwrap().next()
     }

src/rdbc/network/resultset.rs

@@ -11,6 +11,19 @@ use crate::{
     remote_capnp::{bool_box, date_box, int16_box, int32_box, remote_result_set, string_box},
 };
 
+pub struct SetupedImpl {
+    client: bool_box::Client,
+}
+impl SetupedImpl {
+    pub fn new(client: bool_box::Client) -> Self {
+        Self { client }
+    }
+    pub async fn has_value(&self) -> Result<bool> {
+        let reply = self.client.read_request().send().promise.await?;
+        Ok(reply.get()?.get_val())
+    }
+}
+
 pub struct NextImpl {
     client: bool_box::Client,
 }
@@ -234,6 +247,7 @@ impl NetworkResultSet {
 
 impl ResultSetAdapter for NetworkResultSet {
     type Meta = NetworkResultSetMetaData;
+    type Setuped = SetupedImpl;
     type Next = NextImpl;
     type Int16Value = Int16ValueImpl;
     type Int32Value = Int32ValueImpl;
@@ -242,6 +256,17 @@ impl ResultSetAdapter for NetworkResultSet {
     type DateValue = DateValueImpl;
     type Res = ResponseImpl;
 
+    fn before_first(&self) -> Result<Self::Setuped> {
+        let val = self
+            .resultset
+            .before_first_request()
+            .send()
+            .pipeline
+            .get_val();
+
+        Ok(Self::Setuped::new(val))
+    }
+
     fn next(&self) -> Self::Next {
         let exists = self.resultset.next_request().send().pipeline.get_val();
 

src/rdbc/resultsetadapter.rs

@@ -33,6 +33,7 @@ impl fmt::Display for ResultSetError {
 
 pub trait ResultSetAdapter {
     type Meta: ResultSetMetaDataAdapter;
+    type Setuped;
     type Next;
     type Int16Value;
     type Int32Value;
@@ -41,6 +42,7 @@ pub trait ResultSetAdapter {
     type DateValue;
     type Res;
 
+    fn before_first(&self) -> Result<Self::Setuped>;
     fn next(&self) -> Self::Next;
     fn get_i16(&mut self, fldname: &str) -> Result<Self::Int16Value>;
     fn get_i32(&mut self, fldname: &str) -> Result<Self::Int32Value>;