cli: should two statements work in sql shell?

[mberhault]

eg: running the following in the sql client:

root@:15432> select 3; show databases;
+---+
| 3 |
+---+
| 3 |
+---+

I had to change something similar in https://github.com/cockroachdb/cockroach/pull/3757/files#diff-7d7fb132e111ef7398af7150b1d54a32 Example_SQL Line 544. With the cockroach driver, the final result was from the last query. With the postgres driver, only the first query is run.

[tamird]

odd. pgwire should run all queries and return all results.

[knz]

I ran into a similar issue when implementing sql -e. The issue is that the sql.driver.Queryer interface only returns one Rows set, for the last statement in the query. As long as this interface is a single Rows set I do not see how to do anything better.
(short of implementing a full SQL parser on the client side to split semicolons)

[mberhault]

@knz: yup. this is where I found it too. I had to tweak one of your test cases in cli_test.go due to behavior change for multiple statements between the cockroach and pq drivers.

[knz]

Oh wait are you saying that multiple statements simply don't work over pgwire? This is terrible.
I do not care that results are only reported for the last statements, but all statements must execute and an error at any statement must prevent subsequent statements from running. Otherwise #4036 can't work.

[mberhault]

I honestly don't know. I was definitely not getting two sets of results. The behavior change was in getting the result from the first statement instead of the second. I didn't not check whether the second was running or not

[tamird]

If you point psql at cockroach and run two statements, you should observe
the results for both.

On Fri, Jan 29, 2016 at 11:57 AM, marc notifications@github.com wrote:

I honestly don't know. I was definitely not getting two sets of results.
The behavior change was in getting the result from the first statement
instead of the second. I didn't not check whether the second was running or
not

—
Reply to this email directly or view it on GitHub
#4016 (comment)
.

[mberhault]

we definitely run both. eg:

$ ./cockroach sql --dev
oot@:15432> select 3; create database foo;
+---+
| 3 |
+---+
| 3 |
+---+
root@:15432> show databases;
+----------+
| Database |
+----------+
| "foo"    |
| "system" |
+----------+

Our code uses the go interface the way it should, I'm 95% sure the limitation is in the sql driver itself. see golang/go#12382 for the related issue.