Incorrect datatype assigned to a column of type smallint[]

[GetPsyched]

Version

1.13.0

What happened?

I have a column (credits) in a PostgreSQL table whose datatype is smallint[4], an array of 4 smallint types.

When I put the query (given below), a struct is generated and that column has the datatype []int16. The problem I was facing is that the returned object of that struct contained only the values until that column (excluding it). I spent some time figuring out the issue and at the end I found that changing the datatype to []int32 in the auto-generated struct fixed the issue and I got my data as normal.

However, this isn't ideal as the auto-generated struct should not be edited.

Relevant log output

No response

Database schema

CREATE TABLE IF NOT EXISTS course (
    code        char(7) NOT NULL,
    title       varchar(32) NOT NULL,
    branch      char(3) NOT NULL,
    semester    smallint NOT NULL,
    credits     smallint[4] NOT NULL,
    prereq      char(7)[],
    type        char(3) NOT NULL,
    objectives  text NOT NULL,
    content     text NOT NULL,
    books       text NOT NULL,
    outcomes    text NOT NULL,
    PRIMARY KEY (code, branch)
);

SQL queries

-- name: GetAllCourses :many
SELECT * FROM course;

Configuration

version: 1
packages:
  - path: "query"
    name: "query"
    engine: "postgresql"
    schema: "query/schema.sql"
    queries: "query/query.sql"

Playground URL

No response

What operating system are you using?

Linux

What database engines are you using?

PostgreSQL

What type of code are you generating?

Go

[kyleconroy]

smallint maps to a int16, so I'm not sure why changing the array to int32 was necessary. Will take a look

[GetPsyched]

Any updates yet?

[akutschera]

I did some research at it looks like this happens due to the lib/pg driver that is used in your example. For some reason this driver only supports int32 and int64 in arrays (see array.go). When I add an Int16Array there, the struct above can be Scanned. There is an open (ticket) where someone asks about this.

When you use sql_package: "pgx/v4" to generate the code, the example works.

To me it seems that the proper way to fix this is the lib/pg driver. Generating int32 for smallint is just a workaround.

[GetPsyched]

Gotcha. I just hope that the lib/pg devs fix it then, @akutschera?