sql: DDL after write error is misleading #57476
Description
The following error is misleading:
root@localhost:26257/defaultdb> create table foo (i int, j int);
CREATE TABLE
root@localhost:26257/defaultdb> begin;
BEGIN
root@localhost:26257/defaultdb OPEN> insert into foo values (1,2);
INSERT 1
root@localhost:26257/defaultdb OPEN> create table t();
ERROR: unimplemented: schema change statement cannot follow a statement that has written in the same transaction
SQLSTATE: 0A000
HINT: You have attempted to use a feature that is not yet implemented.
See: https://go.crdb.dev/issue-v/26508/v21.1
Although it says "schema change statement cannot follow a statement that has written in the same transaction", one can successfully preform a schema change after a write in a txn:
root@localhost:26257/defaultdb OPEN> create table foo (i int, j int);
CREATE TABLE
root@localhost:26257/defaultdb OPEN> create table bar (j int);
CREATE TABLE
root@localhost:26257/defaultdb> begin;
BEGIN
root@localhost:26257/defaultdb OPEN> alter table bar drop column j;
ALTER TABLE
root@localhost:26257/defaultdb OPEN> insert into foo values (1,2);
INSERT 1
root@localhost:26257/defaultdb OPEN> create table t();
CREATE TABLE
root@localhost:26257/defaultdb OPEN> commit;
COMMIT
The error message should be updated to say that we do not support DDLs if the first write in a txn precedes the first DDL. h in the txn
This issue relates to #54477.