Скачать или смотреть How to Display MySQL Query Results in a cxGrid Using Delphi 5

Learn how to effectively get your MySQL query results to display in a `cxGrid` with this comprehensive guide!
---
This video is based on the question https://stackoverflow.com/q/63459956/ asked by the user 'Keila' ( https://stackoverflow.com/u/9796091/ ) and on the answer https://stackoverflow.com/a/63463724/ provided by the user 'MartynA' ( https://stackoverflow.com/u/2663863/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: How do I get the results of a MySQL Query to display in a cxGrid?

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Displaying MySQL Query Results in cxGrid Using Delphi 5

If you're working with Delphi and trying to display results from a MySQL query in a cxGrid, you're not alone. Many users encounter issues where the grid appears with the correct structure - rows, columns, and lines - but without any actual data. This post will break down the problem, providing clear solutions in organized sections, so you can finally see those query results displayed in your cxGrid.

Understanding the Challenge

You have a setup with the following components:

TDataSource linked to a TMySQLQuery

A configured cxGrid, cxGridLevel, and cxGridDBTableView

After executing your query, although it returns the correct number of results, the cells in your grid remain blank. So what could be going wrong? It may seem complex, but let's break it down into manageable sections.

Steps to Solve the Issue

Follow these steps to troubleshoot and successfully display your query results in the cxGrid:

1. Data Source Configuration

Before diving into the code, double-check that your TDataSource (DSNewKits) is properly configured. It should be linked to your dataset (in this case, NewKitsQry). Here’s a quick reminder of how to set it up:

Ensure DSNewKits.DataSet is correctly assigned to NewKitsQry.

Confirm that DBTableView (like cxNewKitsGridDBTableView1) is utilizing the correct Data Source: cxNewKitsGridDBTableView1.DataController.DataSource := DSNewKits;.

2. Executing the Query

When executing your MySQL query, follow these particular steps to ensure everything is in order:

Set the Enabled property of DSNewKits to false before running the query.

Close NewKitsQry to reset it.

After setting your SQL text, remember to open NewKitsQry before enabling the Data Source again. Here’s how it should look:

[[See Video to Reveal this Text or Code Snippet]]

3. Creating the Grid Items

Once your dataset is opened and ready, ensure that the grid has its items created:

[[See Video to Reveal this Text or Code Snippet]]

This line is crucial as it populates the grid with the corresponding items based on the dataset configuration.

4. Error Handling

To debug where things might be going wrong, you might want to include some error handling in your query execution. For example:

[[See Video to Reveal this Text or Code Snippet]]

This will help you capture any hidden exceptions that might be affecting the display of your data.

Example Code Snippet

To bring all of this together, here’s an example snippet adapted from your current setup to show a successful configuration:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

By following these structured steps, you should be able to troubleshoot your cxGrid and successfully display your MySQL query results. Remember the importance of proper data source assignment, execution order, and creating grid items. With a little patience, you'll see your grid populated with data in no time!

If you have further questions or run into any issues, feel free to reach out for assistance. Happy coding!