问如何使用sqlite fts3执行全文搜索

EN

string createSql = "CREATE VIRTUAL TABLE TweetFts USING FTS3(TweetId, Title, Description)";

string insertSql = "INSERT INTO TweetFts (TweetId, Title, Description) 
     SELECT TweetId, Title, Description FROM Tweet";

string sql = @"select TweetId from TweetFts where Title match '" + allWords + "'";
sql += " union ";
sql += @"select TweetId from TweetFts where Description match '" + allWords + "'";
sql += " union ";
sql += @"select TweetId from TweetFts where Title match '""" + exactMatch + @"""'";
sql += " union ";
sql += @"select TweetId from TweetFts where Description match '""" + exactMatch + @"""'";