Cross-database prepared statement binding (like and where in) in Golang

Question

After reading many tutorials, I found that there are many ways to bind arguments on prepared statement in Go, some of them

SELECT * FROM bla WHERE x = ?col1          


        

Answer 1

I had this same question, and after reading the answers started to look for other solution on how to bind arguments for the IN statement.

Here is an example of what I did, not the most elegant solution, but works for me.

What I did was to create a select query with the parameters statically set on the query, and not using the bind feature at all.

It could be a good idea to sanitize the string that comes from the Marshal command, to be sure and safe, but I don't need it now.

package main

import (
    "database/sql"
    "encoding/json"
    "fmt"
    "log"

    _ "github.com/go-sql-driver/mysql"
)

type Result struct {
    Identifier string
    Enabled    bool
}

func main() {

    // Open connection
    db, err := sql.Open("mysql", "username:password@tcp(server-host)/my-database")
    if err != nil {
        panic(err.Error()) // proper error handling instead of panic in your app
    }
    defer db.Close()

    // this is an example of a variable list of IDs
    idList := []string{"ID1", "ID2", "ID3", "ID4", "ID5", "IDx"}

    // convert the list to a JSON string
    formatted, _ := json.Marshal(idList)

    // a JSON array starts and ends with '[]' respectivelly, so we replace them with '()'
    formatted[0] = '('
    formatted[len(formatted)-1] = ')'

    // create a static select query
    query := fmt.Sprintf("SELECT identifier, is_enabled FROM some_table WHERE identifier in %s", string(formatted))

    // prepare que query
    rows, err := db.Query(query)
    if err != nil {
        panic(err.Error()) // proper error handling instead of panic in your app
    }
    defer rows.Close()

    var result []Result
    // fetch rows
    for rows.Next() {
        var r0 Result
        if err := rows.Scan(&r0.Identifier, &r0.Enabled); err != nil {
            log.Fatal(err)
        }
        // append the row to the result
        result = append(result, r0)
    }
    if err := rows.Err(); err != nil {
        log.Fatal(err)
    }

    fmt.Printf("result = %v\n", result)
}