From 86e97648ddacd3b27f268165f98447a8b71f972b Mon Sep 17 00:00:00 2001
From: qiaojialin <646274302@qq.com>
Date: Fri, 10 Jul 2020 11:33:59 +0800
Subject: [PATCH] check fetch size in query

---
 .../java/org/apache/iotdb/db/service/TSServiceImpl.java     | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/server/src/main/java/org/apache/iotdb/db/service/TSServiceImpl.java b/server/src/main/java/org/apache/iotdb/db/service/TSServiceImpl.java
index dcbbc368c0096..3721d5aa40e36 100644
--- a/server/src/main/java/org/apache/iotdb/db/service/TSServiceImpl.java
+++ b/server/src/main/java/org/apache/iotdb/db/service/TSServiceImpl.java
@@ -142,6 +142,7 @@ public class TSServiceImpl implements TSIService.Iface, ServerContext {
   private static final int MAX_SIZE =
       IoTDBDescriptor.getInstance().getConfig().getQueryCacheSizeInMetric();
   private static final int DELETE_SIZE = 20;
+  private static final int FETCH_SIZE = 10000;
   private static final String ERROR_PARSING_SQL =
       "meet error while parsing SQL to physical plan: {}";
   private static final List<SqlArgument> sqlArgumentList = new ArrayList<>(MAX_SIZE);
@@ -553,6 +554,11 @@ private TSExecuteStatementResp internalExecuteQueryStatement(String statement,
     try {
       TSExecuteStatementResp resp = getQueryResp(plan, username); // column headers
 
+      // In case users forget to set this field in query, use the default value
+      if (fetchSize == 0) {
+        fetchSize = FETCH_SIZE;
+      }
+
       if (plan instanceof ShowTimeSeriesPlan) {
         //If the user does not pass the limit, then set limit = fetchSize and haslimit=false,else set haslimit = true
         if (((ShowTimeSeriesPlan) plan).getLimit() == 0) {