How to Check for Record Existence and Insert if Necessary in Golang?

Checking for Record Existence and Inserting if Non-Existent in Golang

The objective is to check if a record exists in a database and insert it if it does not exist. To achieve this in Golang, one approach is as follows:

To check for existence, you can use the QueryRow function, which returns a row for the specified query. You can then scan this row into a variable using the Scan function. If the scan operation is successful, the variable will be set to true; otherwise, it will remain false.

If the record doesn't exist, you can use the Exec function to execute an INSERT statement and insert the record.

Here's an example of how you can implement this approach:

var exists bool
row := db.QueryRow("SELECT EXISTS(SELECT 1 FROM category WHERE name = 'construction')")
if err := row.Scan(&exists); err != nil {
    return err
} else if !exists {
    if err := db.Exec("INSERT INTO category (name) VALUES ('construction')"); err != nil {
        return err
    }
}

In this example, we're checking for the existence of a record in the category table with the name column value set to 'construction'. If the record doesn't exist, we insert a new record with that value.

You can adapt this approach to check for records in other tables and insert them if necessary.

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