![]() The Inspector now shows the properties for Listbox.Ĭhange the Name property from Listbox1 to TaskList. You need to change the following properties: Name, Column Count, Initial Value, Column Widths and Locking.įirst, in the Layout Editor, click on the Listbox to select it. The Listbox is where the tasks that your user enters are displayed and stored. You can leave Company Name as it is or change it.Ĭlick Create to open the main Xojo window (called the Workspace), where you will begin designing your app. It will automatically populate using what you enter for the Application and Company Names, but you can also change it to whatever you want.Įnter Task Manager as the Application Name. This will be the filename of the actual app file that gets created.Īpplication Identifier: a unique identifier for this app. You should now see three fields that need values: Application Name, Company Name and Application Identifier.Īpplication Name: the name of your app. For this Tutorial, you are building a desktop app, so click on Desktop. Xojo lets you build several different types of apps (Desktop, Web, Console and iOS). If you already had Xojo running, choose File > New Project and click on Desktop in the Project Chooser. After it finishes loading, the Project Chooser window appears. If you haven't done so already, now is the time to start Xojo. Reporting bugs and making feature requests.Starting a transaction varies depending on the database you are using. Lastly, using transactions can improve performance when adding or changing data in the database as the commit operation can be time consuming so if you do it less often (by only committing data that has been added in large chunks) you can improve performance. This prevents people from seeing data before it is ready. Second, for databases that can have multiple users, changes made in a transaction are not usually visible to other users until the transaction is marked as completed (by committing). A failure allows you to revert everything back to its initial state, sort of like an Undo. If an error occurs partway through some changes to several tables, you do not want the data to be missing in some tables. First, it ensures that data integrity is always maintained. When you are using a transaction, changes made to a database are not made permanent until you commit. This is a block of processing that either all completes successfully or none completes successfully. To learn more about general SQL, visit the W3Schools SQL Tutorial.Ĭhanges to a database are made in what is called a transaction. This is optional with some databases, but a semi-colon will be used in code samples for consistency. When you write SQL, as you will see below, it often ends in a semi-colon ( ) character which indicates the "end of the SQL command". This section shows some example of generic SQL that ought to work across most databases. These commands are: SELECT, INSERT, UPDATE, DELETE, COMMIT and ROLLBACK. Regardless, there are several common SQL commands that are always available, even if their specific syntax changes slightly depending on the database you are using. This can make it challenging to switch between database engines (such as SQLite and PostgreSQL, for example) because the SQL used to send commands to the database may be different. But as you create more complex SQL, you'll find that each database has their own slightly different variant of SQL. For simple SQL commands, SQL is often the same across different databases. SQL is the way to send commands to the database to do things such as create tables or get data from tables. The collection of your tables is called the "database schema" or "database design".ĭatabase engines all share a similar command structure, which is called SQL, which stands for Structured Query Language and is often pronounced as "sequel". You can look up the teams for the other players using the same technique. So both Bob and Tom are on the Seagulls team. Looking in the Team table from above, you can see that the team with ID = 1 is the Seagulls. For example, you can see that Bob and Tom both have TeamID = 1. It clearly tells you the team to which the player belongs. This column defines the relationship between Player and Team. But in addition, it also has a TeamID column. Notice that the Player table has its own ID column as well. Here is an example of a Player table with sample data: For example, to track the players for each team you would have another table, called Player, that is related to the Team table. And these tables are often related in some way, which is why these are called relational databases. Reporting bugs and making feature requestsĪ database usually consists of many tables.Considerations when using a database with a web application.
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