Fix for #534 and #535

Author: levkk

Cargo.lock

@@ -270,7 +270,7 @@ username = "sharding_user"
 # if `server_password` is not set.
 password = "sharding_user"
 
-pool_mode = "session"
+pool_mode = "transaction"
 
 # PostgreSQL username used to connect to the server.
 # server_username = "another_user"

pgcat.toml

@@ -997,7 +997,9 @@ impl Server {
             }
         }
 
-        self.deallocate(names).await?;
+        if !names.is_empty() {
+            self.deallocate(names).await?;
+        }
 
         Ok(())
     }
@@ -1013,15 +1015,17 @@ impl Server {
     /// Close a prepared statement on the server.
     pub async fn deallocate(&mut self, names: Vec<String>) -> Result<(), Error> {
         for name in &names {
-            debug!("Deallocating prepared statement `{}`", name);
+            info!("Deallocating prepared statement `{}`", name);
 
             let close = Close::new(name);
             let bytes: BytesMut = close.try_into()?;
 
             self.send(&bytes).await?;
         }
 
-        self.send(&flush()).await?;
+        if !names.is_empty() {
+            self.send(&flush()).await?;
+        }
 
         // Read and discard CloseComplete (3)
         for name in &names {