alter schema change property to a different type (string->int)

[Sophie-Xie]

Prepare the space

(root@nebula) [(none)]> create space test1(vid_type=fixed_string(30))
Execution succeeded (time spent 39512/41812 us)

Tue, 14 Sep 2021 10:27:53 CST

(root@nebula) [(none)]> use test1
[ERROR (-1005)]: SpaceNotFound:

Tue, 14 Sep 2021 10:27:56 CST

(root@nebula) [(none)]> use test1
Execution succeeded (time spent 48813/51626 us)

Tue, 14 Sep 2021 10:27:58 CST

(root@nebula) [test1]> create tag test(col1 string , col2 string);
Execution succeeded (time spent 83144/85189 us)

Tue, 14 Sep 2021 10:38:20 CST

(root@nebula) [test1]> insert vertex test(col1,col2) values "11":("aa","bb");
Execution succeeded (time spent 6843/9300 us)

Tue, 14 Sep 2021 10:38:42 CST

(root@nebula) [test1]> fetch prop on test "11"
+--------------------------------------+
| vertices_                            |
+--------------------------------------+
| ("11" :test{col1: "aa", col2: "bb"}) |
+--------------------------------------+
Got 1 rows (time spent 11830/14468 us)

Tue, 14 Sep 2021 10:38:58 CST

(root@nebula) [test1]> alter tag test change (col2 int)
Execution succeeded (time spent 40178/44064 us)

Tue, 14 Sep 2021 10:41:12 CST

(root@nebula) [test1]> fetch prop on test "11"
+--------------------------------------+
| vertices_                            |
+--------------------------------------+
| ("11" :test{col1: "aa", col2: "bb"}) |
+--------------------------------------+
Got 1 rows (time spent 9940/13559 us)

Tue, 14 Sep 2021 10:41:18 CST

(root@nebula) [test1]> insert vertex test(col1,col2) values "22":("aa",99)
Execution succeeded (time spent 15569/18790 us)

Tue, 14 Sep 2021 10:42:04 CST

(root@nebula) [test1]> create tag index test_index on test(col2);
Execution succeeded (time spent 68325/71791 us)

Tue, 14 Sep 2021 10:42:08 CST

(root@nebula) [test1]> rebuild tag index test_index
+------------+
| New Job Id |
+------------+
| 30         |
+------------+
Got 1 rows (time spent 61606/66416 us)

Tue, 14 Sep 2021 10:42:13 CST

(root@nebula) [test1]> show jobs
+--------+---------------------+------------+-------------------------+-------------------------+
| Job Id | Command             | Status     | Start Time              | Stop Time               |
+--------+---------------------+------------+-------------------------+-------------------------+
| 30     | "REBUILD_TAG_INDEX" | "FINISHED" | 2021-09-14T02:42:13.000 | 2021-09-14T02:42:13.000 |
+--------+---------------------+------------+-------------------------+-------------------------+
Got 1 rows (time spent 17940/20785 us)

Tue, 14 Sep 2021 10:42:17 CST

(root@nebula) [test1]> lookup on test where test.col2 < 99 yield test.col2;
+----------+----------------------+
| VertexID | test.col2            |
+----------+----------------------+
| "11"     | -2134143272594898944 |
+----------+----------------------+
Got 1 rows (time spent 13113/16100 us)

Tue, 14 Sep 2021 10:42:34 CST

from #2671

[Sophie-Xie]

There are other high priority issues to do, this issue will be later to next version.

[critical27]

IMO, when add/change, we require default value or nullable of the added/changed field. As for drop, we'd better just forbid it, drop will raise up more problem.

There is a related problem fo rebuild index https://discuss.nebula-graph.com.cn/t/topic/6376/

[Sophie-Xie]

Talked it offline, all schema problem will fixed in 5.x.