How to execute an IN lookup in SQL using Golang?

Question

What does Go want for the second param in this SQL query. I am trying to use the IN lookup in postgres.

stmt, err := db.Prepare(\"SELECT * FRO         


        

Answer 1

if you use sqlx, you can follow this way: https://github.com/jmoiron/sqlx/issues/346

arr := []string{"this", "that"}
query, args, err := sqlx.In("SELECT * FROM awesome_table WHERE id=10 AND other_field IN (?)", arr)
 
query = db.Rebind(query) // sqlx.In returns queries with the `?` bindvar, rebind it here for matching the database in used (e.g. postgre, oracle etc, can skip it if you use mysql)
rows, err := db.Query(query, args...)

Answer 2

//I tried a different way. A simpler and easier way, maybe not too efficient.
stringedIDs := fmt.Sprintf("%v", ids)
stringedIDs = stringedIDs[1 : len(stringedIDs)-1]
stringedIDs = strings.ReplaceAll(stringedIDs, " ", ",")
query := "SELECT * FROM users WHERE id IN ("  + stringedIDs + ")"
//Then follow your standard database/sql Query
rows, err := db.Query(query)
//error checking
if err != nil {
    // Handle errors
} else {
    // Process rows
}

Answer 3

With PostgreSQL, at least, you have the option of passing the entire array as a string, using a single placeholder:

db.Query("select 1 = any($1::integer[])", "{1,2,3}")

That way, you can use a single query string, and all the string concatenation is confined to the parameter. And if the parameter is malformed, you don't get an SQL injection; you just get something like: ERROR: invalid input syntax for integer: "xyz"

https://groups.google.com/d/msg/golang-nuts/vHbg09g7s2I/RKU7XsO25SIJ