sql: expected 8 arguments, got 0 using `preparex` and `context.context` [duplicate] - go

Question

This question already has answers here:
How do I batch sql statements with package database/sql
(12 answers)
Golang Route for insert - PrepareContext error
(1 answer)
Need to insert struct directly in a PostgreSQL DB
(2 answers)
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My question is not related to that one. My question was mostly on preparex and ctx. I have already done with the implementation using the db.NamedExec and my code is working for those. What I am trying to do here is to understand context.context and preparex. Implement using these two.
CODE SNIPPET:
model.go
type User struct {
ID int `db:"id" json:"id"`
CreatedAt time.Time `db:"created_at" json:"created_at"`
UpdatedAt time.Time `db:"updated_at" json:"updated_at"`
DeletedAt time.Time `db:"deleted_at" json:"deleted_at"`
Username string `db:"username" json:"username"`
Password string `db:"password" json:"password"`
FirstName string `db:"first_name" json:"first_name"`
LastName string `db:"last_name" json:"last_name"`
Phone string `db:"phone" json:"phone"`
Status bool `db:"status" json:"status"`
Addrs []UserAddress
}
Query:
queryInsertUserData = `
INSERT INTO users (id, created_at, updated_at, deleted_at, username, password, first_name, last_name, phone, status) VALUES($1, now(), now(), $2, $3, $4, $5, $6, $7, $8)
`
type queries struct {
insertUserData,
insertAddrData *sqlx.Stmt
}
//prepareStatement is a method for preparing sqlx statement
func (queries *queries) prepareStatement(db *sqlx.DB, query string) (*sqlx.Stmt, error) {
stmt, err := db.Preparex(query) //https://go.dev/doc/database/prepared-statements
if err != nil {
return nil, err
}
return stmt, err
}
constructUserData, err := queries.prepareStatement(db, queryInsertUserData)
queries.insertUserData = constructUserData
Implementation:
// Insert User data
func (postgres *Postgres) InsertUserData(ctx context.Context) (*entity.User, error) {
c := entity.User{}
err := postgres.queries.insertUserData.SelectContext(ctx, &c) //<---here
if err != nil {
return nil, err
}
return &c, nil
}
my ctx is :
ctx = context.WithValue(ctx, "ID", 1)
ctx = context.WithValue(ctx, "Username", "John")
ctx = context.WithValue(ctx, "Password", "pass")
when I am passing to postgres.queries.insertUserData.SelectContext(ctx, &c)
I am getting: sql: expected 8 arguments, got 0
why it is saying got 0? Can anyone help me with this? How to pass ctx and provide the insert query values?

Answer 1

I didn't get the structure of your code, but from the main context (inserting query) you should do something like this:
package main
import (
"context"
"database/sql"
"log"
)
var db *sql.DB
type User struct {
ID int `db:"id" json:"id"`
CreatedAt time.Time `db:"created_at" json:"created_at"`
UpdatedAt time.Time `db:"updated_at" json:"updated_at"`
DeletedAt time.Time `db:"deleted_at" json:"deleted_at"`
Username string `db:"username" json:"username"`
Password string `db:"password" json:"password"`
FirstName string `db:"first_name" json:"first_name"`
LastName string `db:"last_name" json:"last_name"`
Phone string `db:"phone" json:"phone"`
Status bool `db:"status" json:"status"`
Addrs []UserAddress
}
func main() {
users := []User {
{...User 1 data...},
{...User 2 data...},
}
stmt, err := db.Prepare("INSERT INTO users (id, created_at, updated_at, deleted_at, username, password, first_name, last_name, phone, status) VALUES($1, now(), now(), $2, $3, $4, $5, $6, $7, $8)")
if err != nil {
log.Fatal(err)
}
defer stmt.Close() // Prepared statements take up server resources and should be closed after use.
for id, user := range users {
if _, err := stmt.Exec(id+1, user.Username, user.Password,... other data); err != nil {
log.Fatal(err)
}
}
}
also, you can use the Gorm powerful package for using all relational databases.

Answer 2

I use this helper for inserts.
Works with query syntax as follows:
INSERT INTO checks (
status) VALUES (:status)
returning id;
Sample struct
type Row struct {
Status string `db:"status"`
}
// Insert inserts row into table using query SQL command
// table used only for loging, actual table name defined in query
// function expects Query with named parameters
func Insert(ctx context.Context, row interface{}, query string, table string, tx *sqlx.Tx) (int64, error) {
// convert named query to native parameters format
query, args, err := tx.BindNamed(query, row)
if err != nil {
return 0, fmt.Errorf("cannot bind parameters for insert into %q: %w", table, err)
}
var id struct {
Val int64 `db:"id"`
}
err = sqlx.GetContext(ctx, tx, &id, query, args...)
if err != nil {
return 0, fmt.Errorf("cannot insert into %q: %w", table, err)
}
return id.Val, nil
}