procedure TForm1.FormCreate(Sender: TObject);
begin
SQLite3Connection1.Connected:=false;
SQLite3Connection1.DatabaseName:='D:\lazarus\project2\testRUN.db';      //运行时的 数据库
SQLite3Connection1.Connected:=true;
SQLQuery1.Active:=true;
//SQLite3Connection1.GetTableNames(ListBox1.Items,false);//所有表名
SQLite3Connection1.GetFieldNames('userinfo',ListBox1.Items);  //表结构,所有列
end;

 列类型

uses typinfo; 
procedure TForm1.FormCreate(Sender: TObject);
var
DataType: TFieldType;
begin 

DataType:=SQLQuery1.Fields[2].DataType;
ShowMessage(GetEnumName(TypeInfo(TFieldType), Ord(DataType)));
end;

 所有列类型

https://wiki.freepascal.org/Database_field_type/zh_CN