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Fields are what hold the actual record data for each row in a table. Whereas a record could be considered a "row" in a table, a field could be considered a "column" in a table, or a "cell" in a record. The fields are defined at the time of the table creation.
Fields are added to the record definition in the order they are declared. The FairCom DB API .NET API also includes a set of functions that will allow a field to be inserted at a certain place in the record definition and fields can also be deleted from the record definition.
Each field will have a file type (e.g., CT_INTEGER and CT_CHAR in the example below). For more information, see Field Types.
The CTTable.AddField() method will add a new field to the end of the record definition.
// create a new table object
CTTable ATable = new CTTable(ADatabase);
// add two fields to the table record definition
ATable.AddField("Field1", FIELD_TYPE.INTEGER, 4);
ATable.AddField("Field2", FIELD_TYPE.CHARS, 30);
// create the table
ATable.Create("MyTable", CREATE_MODE.NORMAL_CREATE);
Note: Delphi users should use the equivalent method CreateSession() instead of Create().
CTTable.InsertField() inserts a new field before a given field that has already been defined. The CTTable.InsertField() overloaded methods allow you to specify a field index or a field name to identify the position on the record definition that the new field will be inserted. The first field is number 0, the second field is number 1 and so on.
// create a new table object
CTTable ATable = new CTTable(ADatabase);
// add two fields to the table record definition
ATable.AddField( "Field1", FIELD_TYPE.INTEGER, 4);
ATable.AddField( "Field2", FIELD_TYPE.CHARS, 30);
ATable.InsertField("Field2", "Field3", FIELD_TYPE.BOOL, 1);
// create the table
ATable.Create("MyTable", CREATE_MODE.NORMAL_CREATE);
CTTable.DelField() deletes a field from the record definition. The CTTable.DelField() overloaded methods allow the user to specify a field index or a field name to identify the field to delete. The first field is number 0, the second field is number 1, and so on.
// create a new table object
CTTable ATable = new CTTable(ADatabase);
// add two fields to the table record definition
ATable.AddField( "Field1", FIELD_TYPE.INTEGER, 4);
ATable.AddField( "Field2", FIELD_TYPE.CHARS, 30);
// delete field2 from record definition
ATable.DelField("Field2");
// create the table
ATable.Create("MyTable", CREATE_MODE.NORMAL_CREATE);
