MDEV-19160 JSON_DETAILED output unnecessarily verbose

mysql-test/main/func_json.result

@@ -1133,3 +1133,129 @@ DROP TABLE t1;
 #
 # End of 10.4 tests
 #
+#
+# MDEV-19160 JSON_DETAILED output unnecessarily verbose
+#
+create table t200 (a text);
+insert into t200 values
+('{
+  "steps": [
+    {
+      "join_optimization": {
+        "select_id": 1,
+        "steps": [
+          {
+            "rows_estimation": [
+              {
+                "table": "t1",
+                "range_analysis": {
+                  "table_scan": {
+                    "rows": 1000,
+                    "cost": 2e308
+                  },
+                  "potential_range_indexes": [
+                    {
+                      "index": "a_b",
+                      "usable": true,
+                      "key_parts": ["a", "b"]
+                    }
+                  ],
+                  "best_covering_index_scan": {
+                    "index": "a_b",
+                    "cost": 52.195,
+                    "chosen": true
+                  },
+                  "setup_range_conditions": [],
+                  "group_index_range": {
+                    "chosen": false,
+                    "cause": "no group by or distinct"
+                  },
+                  "analyzing_range_alternatives": {
+                    "range_scan_alternatives": [
+                      {
+                        "index": "a_b",
+                        "ranges": ["2 <= a <= 2 AND 4 <= b <= 4", "123"],
+                        "rowid_ordered": true,
+                        "using_mrr": false,
+                        "index_only": true,
+                        "rows": 1,
+                        "cost": 1.1752,
+                        "chosen": true
+                      }
+                    ],
+                    "analyzing_roworder_intersect": {
+                      "cause": "too few roworder scans"
+                    },
+                    "analyzing_index_merge_union": [],
+                    "test_one_line_array":["123"]
+                  },
+                  "chosen_range_access_summary": {
+                    "range_access_plan": {
+                      "type": "range_scan",
+                      "index": "a_b",
+                      "rows": 1,
+                      "ranges": ["2 <= a <= 2 AND 4 <= b <= 4"]
+                    },
+                    "rows_for_plan": 1,
+                    "cost_for_plan": 1.1752,
+                    "chosen": true
+                  }
+                }
+              },
+              {
+                "selectivity_for_indexes": [
+                  {
+                    "index_name": "a_b",
+                    "selectivity_from_index": 0.001
+                  }
+                ],
+                "selectivity_for_columns": [],
+                "cond_selectivity": 0.001
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      "join_execution": {
+        "select_id": 1,
+        "steps": []
+      }
+    }
+  ]
+}');
+select JSON_DETAILED(JSON_EXTRACT(a, '$**.analyzing_range_alternatives')) from t200;
+JSON_DETAILED(JSON_EXTRACT(a, '$**.analyzing_range_alternatives'))
+[
+    {
+        "range_scan_alternatives": 
+        [
+            {
+                "index": "a_b",
+                "ranges": 
+                [
+                    "2 <= a <= 2 AND 4 <= b <= 4",
+                    "123"
+                ],
+                "rowid_ordered": true,
+                "using_mrr": false,
+                "index_only": true,
+                "rows": 1,
+                "cost": 1.1752,
+                "chosen": true
+            }
+        ],
+        "analyzing_roworder_intersect": 
+        {
+            "cause": "too few roworder scans"
+        },
+        "analyzing_index_merge_union": 
+        [],
+        "test_one_line_array": 
+        ["123"]
+    }
+]
+select JSON_LOOSE(JSON_EXTRACT(a, '$**.analyzing_range_alternatives')) from t200;
+JSON_LOOSE(JSON_EXTRACT(a, '$**.analyzing_range_alternatives'))
+[{"range_scan_alternatives": [{"index": "a_b", "ranges": ["2 <= a <= 2 AND 4 <= b <= 4", "123"], "rowid_ordered": true, "using_mrr": false, "index_only": true, "rows": 1, "cost": 1.1752, "chosen": true}], "analyzing_roworder_intersect": {"cause": "too few roworder scans"}, "analyzing_index_merge_union": [], "test_one_line_array": ["123"]}]

mysql-test/main/func_json.test

@@ -718,3 +718,103 @@ DROP TABLE t1;
 --echo #
 --echo # End of 10.4 tests
 --echo #
+
+
+--echo #
+--echo # MDEV-19160 JSON_DETAILED output unnecessarily verbose
+--echo #
+
+create table t200 (a text);
+
+insert into t200 values
+('{
+  "steps": [
+    {
+      "join_optimization": {
+        "select_id": 1,
+        "steps": [
+          {
+            "rows_estimation": [
+              {
+                "table": "t1",
+                "range_analysis": {
+                  "table_scan": {
+                    "rows": 1000,
+                    "cost": 2e308
+                  },
+                  "potential_range_indexes": [
+                    {
+                      "index": "a_b",
+                      "usable": true,
+                      "key_parts": ["a", "b"]
+                    }
+                  ],
+                  "best_covering_index_scan": {
+                    "index": "a_b",
+                    "cost": 52.195,
+                    "chosen": true
+                  },
+                  "setup_range_conditions": [],
+                  "group_index_range": {
+                    "chosen": false,
+                    "cause": "no group by or distinct"
+                  },
+                  "analyzing_range_alternatives": {
+                    "range_scan_alternatives": [
+                      {
+                        "index": "a_b",
+                        "ranges": ["2 <= a <= 2 AND 4 <= b <= 4", "123"],
+                        "rowid_ordered": true,
+                        "using_mrr": false,
+                        "index_only": true,
+                        "rows": 1,
+                        "cost": 1.1752,
+                        "chosen": true
+                      }
+                    ],
+                    "analyzing_roworder_intersect": {
+                      "cause": "too few roworder scans"
+                    },
+                    "analyzing_index_merge_union": [],
+                    "test_one_line_array":["123"]
+                  },
+                  "chosen_range_access_summary": {
+                    "range_access_plan": {
+                      "type": "range_scan",
+                      "index": "a_b",
+                      "rows": 1,
+                      "ranges": ["2 <= a <= 2 AND 4 <= b <= 4"]
+                    },
+                    "rows_for_plan": 1,
+                    "cost_for_plan": 1.1752,
+                    "chosen": true
+                  }
+                }
+              },
+              {
+                "selectivity_for_indexes": [
+                  {
+                    "index_name": "a_b",
+                    "selectivity_from_index": 0.001
+                  }
+                ],
+                "selectivity_for_columns": [],
+                "cond_selectivity": 0.001
+              }
+            ]
+          }
+        ]
+      }
+    },
+    {
+      "join_execution": {
+        "select_id": 1,
+        "steps": []
+      }
+    }
+  ]
+}');
+
+
+select JSON_DETAILED(JSON_EXTRACT(a, '$**.analyzing_range_alternatives')) from t200;
+select JSON_LOOSE(JSON_EXTRACT(a, '$**.analyzing_range_alternatives')) from t200;

mysql-test/main/opt_trace_ucs2.result

@@ -23,17 +23,13 @@ EXPLAIN
 select JSON_DETAILED(JSON_EXTRACT(trace, '$**.analyzing_range_alternatives')) from INFORMATION_SCHEMA.OPTIMIZER_TRACE;
 JSON_DETAILED(JSON_EXTRACT(trace, '$**.analyzing_range_alternatives'))
 [
-    
     {
         "range_scan_alternatives": 
         [
-            
             {
                 "index": "col1",
                 "ranges": 
-                [
-                    "(a) <= (col1)"
-                ],
+                ["(a) <= (col1)"],
                 "rowid_ordered": false,
                 "using_mrr": false,
                 "index_only": false,
@@ -47,8 +43,7 @@ JSON_DETAILED(JSON_EXTRACT(trace, '$**.analyzing_range_alternatives'))
             "cause": "too few roworder scans"
         },
         "analyzing_index_merge_union": 
-        [
-        ]
+        []
     }
 ]
 drop table t1;

mysql-test/main/range_notembedded.result

@@ -20,7 +20,6 @@ select json_detailed(JSON_EXTRACT(trace, '$**.ranges'))
 from information_schema.optimizer_trace;
 json_detailed(JSON_EXTRACT(trace, '$**.ranges'))
 [
-    
     [
         "(1) <= (key1) <= (1)",
         "(2) <= (key1) <= (2)",

mysql-test/suite/plugins/r/multiauth.result

@@ -110,16 +110,13 @@ json_detailed(priv)
     "authentication_string": "*7D8C3DF236D9163B6C274A9D47704BC496988460",
     "auth_or": 
     [
-        
         {
             "plugin": "ed25519",
             "authentication_string": "F4aF8bw7130VaRbdLCl4f/P/wkjDmgJXwWvpJ5gmsZc"
         },
-        
         {
             "plugin": "unix_socket"
         },
-        
         {
         }
     ],

sql/item_jsonfunc.cc

@@ -257,16 +257,22 @@ static int json_nice(json_engine_t *je, String *nice_js,
                      Item_func_json_format::formats mode, int tab_size=4)
 {
   int depth= 0;
-  const char *comma, *colon;
+  static const char *comma= ", ", *colon= "\": ";
   uint comma_len, colon_len;
   int first_value= 1;
-
-  DBUG_ASSERT(je->s.cs == nice_js->charset());
+  int value_size = 0;
+  int curr_state= -1;
+  int64_t value_len= 0;
+  String curr_str{};
+  
+  nice_js->length(0);
+  nice_js->set_charset(je->s.cs);
+  nice_js->alloc(je->s.str_end - je->s.c_str + 32);
+  
+  
   DBUG_ASSERT(mode != Item_func_json_format::DETAILED ||
               (tab_size >= 0 && tab_size <= TAB_SIZE_LIMIT));
 
-  comma= ", ";
-  colon= "\": ";
   if (mode == Item_func_json_format::LOOSE)
   {
     comma_len= 2;
@@ -285,6 +291,7 @@ static int json_nice(json_engine_t *je, String *nice_js,
 
   do
   {
+    curr_state= je->state;
     switch (je->state)
     {
     case JST_KEY:
@@ -307,7 +314,7 @@ static int json_nice(json_engine_t *je, String *nice_js,
             append_tab(nice_js, depth, tab_size))
           goto error;
 
-        nice_js->append("\"", 1);
+        nice_js->append('"');
         append_simple(nice_js, key_start, key_end - key_start);
         nice_js->append(colon, colon_len);
       }
@@ -332,17 +339,23 @@ static int json_nice(json_engine_t *je, String *nice_js,
         if (append_simple(nice_js, je->value_begin,
                           je->value_end - je->value_begin))
           goto error;
-
+        
+        curr_str.copy((const char *)je->value_begin,
+                      je->value_end - je->value_begin, je->s.cs);
+        value_len= je->value_end - je->value_begin;
         first_value= 0;
+        if (value_size != -1)
+          value_size++;
       }
       else
       {
         if (mode == Item_func_json_format::DETAILED &&
-            depth > 0 &&
+            depth > 0 && !(curr_state != JST_KEY) &&
             append_tab(nice_js, depth, tab_size))
           goto error;
         nice_js->append((je->value_type == JSON_VALUE_OBJECT) ? "{" : "[", 1);
         first_value= 1;
+        value_size= (je->value_type == JSON_VALUE_OBJECT) ? -1: 0;
         depth++;
       }
 
@@ -351,11 +364,27 @@ static int json_nice(json_engine_t *je, String *nice_js,
     case JST_OBJ_END:
     case JST_ARRAY_END:
       depth--;
-      if (mode == Item_func_json_format::DETAILED &&
+      if (mode == Item_func_json_format::DETAILED && (value_size > 1 || value_size == -1) &&
           append_tab(nice_js, depth, tab_size))
         goto error;
+        
+      if (mode == Item_func_json_format::DETAILED && 
+          value_size == 1 && je->state != JST_OBJ_END)
+      {
+        for (auto i = 0; i < value_len; i++)
+        {
+          nice_js->chop();
+        }
+        for (auto i = 0; i < (depth + 1) * tab_size + 1; i++)
+        {
+          nice_js->chop();
+        }
+        nice_js->append(curr_str);
+      }
+      
       nice_js->append((je->state == JST_OBJ_END) ? "}": "]", 1);
       first_value= 0;
+      value_size= -1;
       break;
 
     default: