在SQLite.swift中创建数据库后插入初始数据

Question

I have a SQLite database that I want to populate with some initial data.

Using SQLite.swift , this method seems to be working:

do {
    let _ = try db.run( userDictionary.create(ifNotExists: false) {t in
        t.column(wordId, primaryKey: true)
        t.column(word, unique: true)
        t.column(frequency, defaultValue: 1)
        t.column(following, defaultValue: "")
        })

} catch _ {
    print("table already exists")
    return
}

// Add some initial data for a new database
print("adding new data")
myMethodToInsertInitialData()

The way this works, though is that I am using ifNotExists: false to throw an error every time after the initial database creation. (Setting it to true would not throw an error (or allow the early return).) However, throwing an error on purpose every time except the first time seems like poor programming. I don't really mean it as an error. I just want to insert some data in a newly created database. Is there a better way to do this or is this what everyone does?

Answer 1

To check whether data is available in table or not in SQLite.swift

do
{
    db = try Connection(YOUR_DB_PATH)
    let intCount : Int64  = db.scalar("SELECT count(*) FROM yourTableName") as! Int64
    if (intCount == 0)
    {
        //callWebServiceCall()
    }
    else
    {
        //getDataFromDB()
    }
}
catch
{
    print("error")
}