fix group_concat truncate bug

src/sql/engine/aggregate/ob_aggregate_function.cpp

@@ -2215,7 +2215,18 @@ int ObAggregateFunction::get_result(ObNewRow &row, const common::ObTimeZoneInfo
                       ret = OB_ERR_TOO_LONG_STRING_IN_CONCAT;
                       LOG_WARN("result of string concatenation is too long", K(ret), K(pos), K(append_len), K(concat_str_max_len));
                     } else {
-                      LOG_USER_WARN(OB_ERR_CUT_VALUE_GROUP_CONCAT, gconcat_cur_row_num_ + 1);
+                      int64_t well_formed_len = 0;
+                      int32_t well_formed_error = 0;
+                      if (OB_FAIL(ObCharset::well_formed_len(cexpr->get_collation_type(),
+                                                             sep_str.ptr(),
+                                                             append_len,
+                                                             well_formed_len,
+                                                             well_formed_error))) {
+                        LOG_WARN("invalid string for charset", K(ret), K(cs_type), K(sep_str));
+                      } else {
+                        append_len = well_formed_len;
+                        LOG_USER_WARN(OB_ERR_CUT_VALUE_GROUP_CONCAT, gconcat_cur_row_num_ + 1);
+                      }
                     }
                   }
                   if (OB_FAIL(ret)) {
@@ -2260,7 +2271,18 @@ int ObAggregateFunction::get_result(ObNewRow &row, const common::ObTimeZoneInfo
                           ret = OB_ERR_TOO_LONG_STRING_IN_CONCAT;
                           LOG_WARN("result of string concatenation is too long", K(ret), K(concat_str_max_len));
                         } else {
-                          LOG_USER_WARN(OB_ERR_CUT_VALUE_GROUP_CONCAT, gconcat_cur_row_num_ + 1);
+                          int64_t well_formed_len = 0;
+                          int32_t well_formed_error = 0;
+                          if (OB_FAIL(ObCharset::well_formed_len(cexpr->get_collation_type(),
+                                                                 tmp_str.ptr(),
+                                                                 append_len,
+                                                                 well_formed_len,
+                                                                 well_formed_error))) {
+                            LOG_WARN("invalid string for charset", K(ret), K(cs_type), K(tmp_str));
+                          } else {
+                            append_len = well_formed_len;
+                            LOG_USER_WARN(OB_ERR_CUT_VALUE_GROUP_CONCAT, gconcat_cur_row_num_ + 1);
+                          }
                         }
                       }
                       if (OB_FAIL(ret)) {

src/sql/engine/aggregate/ob_aggregate_processor.cpp

@@ -2620,6 +2620,7 @@ int ObAggregateProcessor::process_aggr_result(const ObChunkDatumStore::StoredRow
 
 int ObAggregateProcessor::extend_concat_str_buf(
   const ObString &pad_str,
+  const ObCollationType cs_type,
   const int64_t pos,
   const int64_t group_concat_cur_row_num,
   int64_t &append_len,
@@ -2659,7 +2660,18 @@ int ObAggregateProcessor::extend_concat_str_buf(
         LOG_WARN("result of string concatenation is too long", K(ret),
                 K(pad_str.length()), K(pos), K(concat_str_max_len_));
       } else {
-        LOG_USER_WARN(OB_ERR_CUT_VALUE_GROUP_CONCAT, group_concat_cur_row_num + 1);
+        int64_t well_formed_len = 0;
+        int32_t well_formed_error = 0;
+        if (OB_FAIL(ObCharset::well_formed_len(cs_type,
+                                               pad_str.ptr(),
+                                               append_len,
+                                               well_formed_len,
+                                               well_formed_error))) {
+          LOG_WARN("invalid string for charset", K(ret), K(cs_type), K(pad_str));
+        } else {
+          append_len = well_formed_len;
+          LOG_USER_WARN(OB_ERR_CUT_VALUE_GROUP_CONCAT, group_concat_cur_row_num + 1);
+        }
       }
     }
   }
@@ -2900,6 +2912,7 @@ int ObAggregateProcessor::collect_aggr_result(
         int64_t group_concat_cur_row_num = 0;
         bool first_item_printed = false;
         const int64_t group_concat_param_count = aggr_info.group_concat_param_count_;
+        const ObCollationType cs_type = aggr_info.expr_->datum_meta_.cs_type_;
         while(OB_SUCC(ret)
               && !buf_is_full
               && OB_SUCC(extra->get_next_row(storted_row))) {
@@ -2916,7 +2929,7 @@ int ObAggregateProcessor::collect_aggr_result(
             if (group_concat_cur_row_num != 0) {
               int64_t append_len = sep_str.length();
               if (OB_FAIL(extend_concat_str_buf(
-                  sep_str, pos, group_concat_cur_row_num, append_len, buf_is_full))) {
+                  sep_str, cs_type, pos, group_concat_cur_row_num, append_len, buf_is_full))) {
                 LOG_WARN("failed to extend concat str buf", K(ret));
               } else if (cur_concat_buf_len_ < append_len + pos) {
                 ret = OB_ERR_UNEXPECTED;
@@ -2931,7 +2944,7 @@ int ObAggregateProcessor::collect_aggr_result(
             for (int64_t i = 0; OB_SUCC(ret) && !buf_is_full && i < group_concat_param_count; ++i) {
               const ObString cell_string = storted_row->cells()[i].get_string();
               int64_t append_len = cell_string.length();
-              if (OB_FAIL(extend_concat_str_buf(cell_string, pos,
+              if (OB_FAIL(extend_concat_str_buf(cell_string, cs_type, pos,
                   group_concat_cur_row_num, append_len, buf_is_full))) {
                 LOG_WARN("failed to extend concat str buf", K(ret));
               } else if (cur_concat_buf_len_ < append_len + pos) {

src/sql/engine/aggregate/ob_aggregate_processor.h

@@ -735,6 +735,7 @@ private:
     const ObAggrInfo &aggr_info,
     const int64_t max_cnt);
   int extend_concat_str_buf(const ObString &pad_str,
+                            const ObCollationType cs_type,
                             const int64_t pos,
                             const int64_t group_concat_cur_row_num,
                             int64_t &append_len,

tools/deploy/mysql_test/test_suite/static_engine/t/expr_concat.test

@@ -69,7 +69,13 @@ set group_concat_max_len=10485;
 select length(group_concat(c1)) from t111_var;
 select group_concat(c1) from t111_var;
 
+set group_concat_max_len=29;
+select group_concat('中文' separator '分隔') from t111_var;
+set group_concat_max_len=23;
+select group_concat('中文' separator '分隔') from t111_var;
+
 set group_concat_max_len=1024;
+drop table t1, t111_var;
 --enable_warnings
 
 connection syscon;