Question

我正在使用ORMLite，使用Table RecentSearch：

@DatabaseTable(tableName = LocalStorageConfig.SQL_RECENTS_TABLE_NAME)
public class RecentSearch {

    @DatabaseField
    public String search_text;
    public static String SQL_SEARCH_FIELD = "search_text";

    @DatabaseField
    public String location_text;
    public static String SQL_LOCATION_FIELD = "location_text";

    @DatabaseField
    public Date creation_date = new Date();
    public static String SQL_CREATION_DATE_FIELD = "creation_date";

它几乎一直在工作，但当我发现包含'的字符串的情况时，它似乎是一个问题。你知道怎么解决这个问题吗？我找不到我想要的东西。

这是我删除最近的

的功能

public boolean deleteRecent(RecentSearch search) {
    try {
        Dao<RecentSearch, Integer> recentsDao = recentsSqlManager.getRecentsDao();
        DeleteBuilder<RecentSearch, Integer> deleteBuilder = recentsDao.deleteBuilder();

        deleteBuilder.where().eq(RecentSearch.SQL_SEARCH_FIELD, search.getSearch_text()).and().eq(RecentSearch.SQL_LOCATION_FIELD, search.location_text);
        recentsDao.delete(deleteBuilder.prepare());
        return true;
    } catch (Exception e) {
        Log.e(TAG, "Database exception", e);
        return false;
    }
}

以下是我得到的例外情况：

java.sql.SQLException: Problems executing Android statement: DELETE FROM `recent_searches` WHERE (`search_text` = '' AND `location_text` = 'Villefranche-d'Allier, Allier' ) 
    at com.j256.ormlite.misc.SqlExceptionUtil.create(SqlExceptionUtil.java:22)
    at com.j256.ormlite.android.AndroidCompiledStatement.runUpdate(AndroidCompiledStatement.java:66)
    at com.j256.ormlite.stmt.StatementExecutor.delete(StatementExecutor.java:425)
    at com.j256.ormlite.dao.BaseDaoImpl.delete(BaseDaoImpl.java:347)
...
Caused by: android.database.sqlite.SQLiteException: near "Allier": syntax error: , while compiling: DELETE FROM `recent_searches` WHERE (`search_text` = '' AND `location_text` = 'Villefranche-d'Allier, Allier' ) 
    at android.database.sqlite.SQLiteCompiledSql.native_compile(Native Method)
    at android.database.sqlite.SQLiteCompiledSql.compile(SQLiteCompiledSql.java:92)
    at android.database.sqlite.SQLiteCompiledSql.<init>(SQLiteCompiledSql.java:65)
    at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:83)
    at android.database.sqlite.SQLiteStatement.<init>(SQLiteStatement.java:41)
    at android.database.sqlite.SQLiteDatabase.compileStatement(SQLiteDatabase.java:1149)

Answer 1

在ORMLite中，当您尝试使用引号构建查询时，应使用SelectArg功能，该功能将使用SQL生成查询？参数然后直接将字符串传递给预准备语句。这解决了转义特殊字符的任何问题，并保护您免受SQL注入安全问题的影响。请参阅documentation on SelectArg。

使用SelectArg，您可以执行以下操作：

DeleteBuilder<RecentSearch, Integer> deleteBuilder = recentsDao.deleteBuilder();

// create our argument which uses a SQL ?
SelectArg locationArg = new SelectArg(search.location_text);
deleteBuilder.where().eq(RecentSearch.SQL_SEARCH_FIELD, search.getSearch_text())
    .and().eq(RecentSearch.SQL_LOCATION_FIELD, locationArg);
recentsDao.delete(deleteBuilder.prepare());
...

Answer 2

绑定到查询时可以使用SelectArg对象，因为它会转义任何引号，因此它们不会生成无效的sql。

带引号的ORMLite查询，Android

2 个答案: