How to update postgres JSONB with variable params in golang? - postgresql

Question

I have a table in cockroachdb/postgres as below:
column_name | data_type | is_nullable | column_default | generation_expression | indices | is_hidden
+-------------+-----------+-------------+----------------+--------------------+-----------+-----------+
id | STRING | false | NULL | | {primary} | false
student | JSONB | true | NULL | | {} | false
(2 rows)
id | student
+--------------------+----------------------------------------------+
1 | {"name": "Albert"}
2 | {"name": "Bob", "state": "CA"}
I am trying to update student with variable number of params - for example, some times update age, some times update age and country etc. How do we do this in golang?
Here is what I have so far, but it does not work.
package main
import (
"database/sql"
"fmt"
_ "github.com/lib/pq"
)
var (
DB = "testdb"
DBUSER = "testuser"
TESTTABLE = "ttab"
CONNSTR = "dbname=" + DB + " user=" + DBUSER + " host=localhost port=26257 sslmode=disable"
DBDRIVER = "postgres"
)
var (
NAME = "name"
AGE = "age"
STATE = "state"
COUNTRY = "country"
)
func update(si map[string]string, id string) error {
silen := len(si)
if silen == 0 {
return fmt.Errorf("si cannot be empty")
}
keys := []string{}
values := []string{}
for k, v := range si {
keys = append(keys, k)
values = append(values, v)
}
db, err := sql.Open(DBDRIVER, CONNSTR)
if err != nil {
return err
}
defer db.Close()
sqlCmd := "UPDATE " + TESTTABLE + " SET student = student || jsonb_object($1, $2) WHERE id = $3"
_, err := db.Exec(sqlCmd, keys, values, id)
return err
}
func main() {
s := make(map[string]string)
s[AGE] = "22"
s[COUNTRY] = "USA"
if err := updateFast3DB(s3, "1"); err != nil {
fmt.Printf("err: %v\n", err)
}
}
Error:
[root#bin]# ./updatedb
update error: sql: converting argument $1 type: unsupported type []string, a slice of string
[root#bin]#

Answer 1

For anyone coming to this later, make sure to read libpq's documentation on passing array values to the driver.
To pass an array into the libpq driver, you must wrap the slice in a pq.Array first. In the example above, the code should look like this:
_, err := db.Exec(sqlCmd, pq.Array(keys), pq.Array(values), id)