FireDAC.GetFieldNames Sample

This sample shows how to populate a string list with some data from a database.

Location

You can find the GetFieldNames sample project at:

• Start | Programs | Embarcadero RAD Studio Rio | Samples and then navigate to:
  • Object Pascal\Database\FireDAC\Samples\Comp Layer\TFDConnection\GetFieldNames
• Subversion Repository:
  • You can find Delphi code samples in GitHub Repositories. Search by name into the samples repositories according to your RAD Studio version.

Description

The GetFieldNames sample shows how to populate a string list with some metadata from a database. To this end, the sample uses the following methods of the TFDConnection component:

• GetTableNames populates a string list with the names of tables in a database.
• GetFieldNames populates a string list with the names of fields in a table.
• GetKeyFieldNames populates a string list with the names of the key fields in a table.

How to Use the Sample

1. Navigate to the location given above and open GetFieldNames.dproj.
2. Press F9 or choose Run > Run.
3. Click on the Use Connection Definition combo box and select a database.
   • It populates the list box component labeled as Tables with the names of tables contained in this database.
   • The first item of the Tables list is automatically selected, which fills the list box components labeled as Fields and Key Fields.
   • Click on a different item of the Tables list to see the list of fields and key fields contained in the selected table.

Files

File in Delphi	Contains
GetFieldNames.dproj GetFieldNames.dpr	The project itself.
fGetFieldNames.pas fGetFieldNames.fmx	The main form.

Implementation

The sample implements the following database related features.

Define a connection to a database

To connect to a database, click on the combo box labeled as Use Connection Definition and choose a database.

Get the table names

The sample populates the list box named lbxTables with the name of the tables of the chosen database. The first item of the lbxTables list is automatically selected. To this end, the sample uses a OnClick event and the GetTableNames method. See the following code:

//...
dmlMainComp.dbMain.GetTableNames('', '', '', lbxTables.Items);
lbxTables.ItemIndex := 0;

Get the field names

When you select an item (a table) of the lbxTables list box, the sample populates the list box named lbxFields with the fild names contained on the selected table. To do this, the sample use an OnClick event ant the GetFieldNames method. See the following code:

//...
with lbxTables do begin
  dmlMainComp.dbMain.GetFieldNames('', '', Items[ItemIndex], '', lbxFields.Items);

Get the key field names

When you select an item (a table) of the lbxTables list box, the sample populates the list box named lbxKeyFields with the key field names contained on the selected table. To do this, the sample use an OnClick event and the GetKeyFieldNames method. See the following code:

//...
with lbxTables do begin
  dmlMainComp.dbMain.GetKeyFieldNames('', '', Items[ItemIndex], '', lbxKeyFields.Items);

Uses

• TFDConnection
• GetTableNames
• GetFieldNames
• GetKeyFieldNames

See Also

• FireDAC
• Obtaining Metadata
• Retrieving Information About a Session

Samples

• FireDAC Info Report sample
• FireDAC Pooling sample
• FireDAC Transactions sample