Date: 2019-08-05 11:49:03 +0200
From: xavier <>
To: clients devs <>
Version: -- development
CC: @PedroTadim, @yzchang

Last updated: 2019-09-02 16:05:26 +0200

Comment 27199

Date: 2019-08-05 11:49:03 +0200
From: xavier <>

User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/75.0.3770.100 Safari/537.36
Build Identifier:

When I use mapi to execute the statement "alter table tb1 rename to tb2", I got message:no such table.But i can see the new tablename when use "\d".
It is ok to use mclient directly.

Finally I can only restart the database "monetdb stop dbname1; monetdb start dbname1;"when using mapi.

Reproducible: Always

Steps to Reproduce:

1.mapi_query("alter table tb1 rename to tb2")
2.mclient, \d. Tablename has changed.
3.execute "select * from tb2", ereport"no such table."

Actual Results:

no such table tb2.

Comment 27201

Date: 2019-08-05 13:50:08 +0200
From: @PedroTadim

Hello Xavier,

I can't reproduce your error. Can you try to reproduce it on the Apr2019 branch?
If not, can you tell which revision are you testing in? The development branch is often under modification and it is not advisable for regular usage.

Best regards,
Pedro

Comment 27202

Date: 2019-08-06 15:19:29 +0200
From: MonetDB Mercurial Repository <>

Changeset 240face86605 made by Pedro Ferreira pedro.ferreira@monetdbsolutions.com in the MonetDB repo, refers to this bug.

For complete details, see https//devmonetdborg/hg/MonetDB?cmd=changeset;node=240face86605

Changeset description:

Added test for table rename with concurrent clients, similar to bug #6741.

Comment 27204

Date: 2019-08-07 09:47:45 +0200
From: xavier <>

This bug is similar to the following：
I use mclient to connect MonetDB and enter this sql:"alter table t1 rename to t2",then I keep this mclient alive and I use anthor mclient to connect the same MonetDB database, but when I enter this sql :"select *from t2 ",MonetDB reports an error : "no such table "t2"". It seems that only one connection could take effect.So how can I make all connection take effect?
This is Linux OS, actually it is Centos 7.5. MonetDB's version is 2019,April.
In mclient A ,I enter this sql:
alter table t1 rename to t2;
then I keep mclient A alive, I use another mclient B to connect the same database, the I enter this sql:
select * from t2;
then I got an error: no such table t2. Restart this database could solve this problem.
I expect the output is the data of t2,but the actual output is ERROR,no such table t2

Comment 27205

Date: 2019-08-07 12:23:37 +0200
From: MonetDB Mercurial Repository <>

Changeset 319ffe87a9a8 made by Pedro Ferreira pedro.ferreira@monetdbsolutions.com in the MonetDB repo, refers to this bug.

For complete details, see https//devmonetdborg/hg/MonetDB?cmd=changeset;node=319ffe87a9a8

Changeset description:

When a transaction starts, the reset code gets called. Make sure to apply possible name changes on schemas, tables or columns.

This hopefully fixes bug #6741.

Comment 27206

Date: 2019-08-07 12:55:15 +0200
From: @yzchang

It works for me.

Jennie

Comment 27226

Date: 2019-08-15 08:22:10 +0200
From: xavier <>

It is similar to table rename error.I execute 'alter table tb1 rename id1 to id2' on one mclient，i get message "0 tuples! 1 column dropped!" when execute 'select id2 from tb1'on another mclient.It doesn't work.

Comment 27227

Date: 2019-08-15 13:39:27 +0200
From: @yzchang

Hai exact changeset are you using? I just checked out the current tip of Apr2019 (hg id: 382d15e2f110), and it works for me. Please double check that you have the most recent code.

Also, the message "0 tuples! 1 column dropped!" is a bit weird. Rename column doesn't say this:

sql>alter table t1 rename i to j;
operation successful

Comment 27228

Date: 2019-08-16 04:20:07 +0200
From: xavier <>

This may be my fault.
I got the error message using the current tip of Apr2019 (git id: 7bc14c3).
When i update to the most recent code, it is correct.