我把它想出来了来自newtover的灵感，深入研究FMDB并重新阅读 sqlite3 文档（在我看来，它仍然非常模糊）。当我对需要迁移的模式进行显着更改时，此代码返回我在管理工具中遇到的值。

I figured it out with the inspiration from newtover, digging into FMDB and re-reading the sqlite3 documentation (it is still very vague in my opinion). This code returns the value that I bumped in the admin tool when I make notable changes to the schema that require migration.

-(int)queryUserVersion: (sqlite3*) db {
    // get current database version of schema
    static sqlite3_stmt *stmt_version;
    int databaseVersion;

    if(sqlite3_prepare_v2(db, "PRAGMA user_version;", -1, &stmt_version, NULL) == SQLITE_OK) {
        while(sqlite3_step(stmt_version) == SQLITE_ROW) {
            databaseVersion = sqlite3_column_int(stmt_version, 0);
            NSLog(@"%s: version %d", __FUNCTION__, databaseVersion);
        }
        NSLog(@"%s: the databaseVersion is: %d", __FUNCTION__, databaseVersion);
    } else {
        NSLog(@"%s: ERROR Preparing: , %s", __FUNCTION__, sqlite3_errmsg(db) );
    }
    sqlite3_finalize(stmt_version);

    return databaseVersion;
}

我有一个类似的方法，用于修改sql语句的模式版本到PRAGMA schema_version;

I have a similar method for the schema version where the sql-statement is changed to "PRAGMA schema_version;"