fix: panic when result is empty (#26)

src/meta/telemetry.rs

@@ -1,6 +1,6 @@
-use std::collections::HashMap;
 use segment::{message::Track, Client, Message};
 use serde_json::Value;
+use std::collections::HashMap;
 
 use crate::infra::config::{CONFIG, INSTANCE_ID, STREAM_SCHEMAS, TELEMETRY_CLIENT, USERS, VERSION};
 

src/service/search/exec.rs

@@ -148,7 +148,7 @@ pub async fn search(
         Some(batches) => batches.to_owned(),
         None => Vec::new(),
     };
-    if !result_query.is_empty() {
+    if !result_query.is_empty() && !result_query[0].is_empty() {
         let schema = result_query[0][0].schema();
         let ipc_options = ipc::writer::IpcWriteOptions::default();
         let ipc_options = ipc_options