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我正在使用 android sqlite 数据库，我想使用带有 where 子句的 sql select 语句选择一个指定的查询，例如 "SELECT * FROM mytable WHERE name = 'Name'";

但我没有成功，这是我的代码，但不包含任何 where 子句。谢谢。

public String Read(String name)
{
    String[] columns = new String[]{SQLiteHelper.COLUMN_NPM, SQLiteHelper.COLUMN_NAME};
    String selection = SQLiteHelper.COLUMN_NAME + " = " + name;
    String[] selectionArgs = {String.valueOf(name)};
    Cursor cursor = database.query(SQLiteHelper.TABLE_MHS, columns, selection, selectionArgs, null, null, null);


    cursor.moveToFirst();
    String index_name = cursor.getString(cursor.getColumnIndex(SQLiteHelper.COLUMN_NAME));
    return index_name;
}

我将该代码放在扩展 sqliteopenhelper 的数据库源中，但在 log cat 中出现以下错误

03-10 11:57:37.000: E/AndroidRuntime(14709): FATAL EXCEPTION: main 03-10 11:57:37.000: E/AndroidRuntime(14709): android.database.sqlite.SQLiteException: no such column: radit: , while compiling: SELECT npm, name FROM Mhs WHERE name = radit 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.database.sqlite.SQLiteCompiledSql.native_compile(Native Method) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.database.sqlite.SQLiteCompiledSql.compile(SQLiteCompiledSql.java:92) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.database.sqlite.SQLiteCompiledSql.<init>(SQLiteCompiledSql.java:65) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:83) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.database.sqlite.SQLiteQuery.<init>(SQLiteQuery.java:49) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:53) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1438) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1317) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1271) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1353) 03-10 11:57:37.000: E/AndroidRuntime(14709): at com.crud.MhsDataSource.Read(MhsDataSource.java:55) 03-10 11:57:37.000: E/AndroidRuntime(14709): at com.crud.MainActivity$4.onClick(MainActivity.java:76) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.view.View.performClick(View.java:2533) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.view.View$PerformClick.run(View.java:9320) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.os.Handler.handleCallback(Handler.java:587) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.os.Handler.dispatchMessage(Handler.java:92) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.os.Looper.loop(Looper.java:150) 03-10 11:57:37.000: E/AndroidRuntime(14709): at android.app.ActivityThread.main(ActivityThread.java:4389) 03-10 11:57:37.000: E/AndroidRuntime(14709): at java.lang.reflect.Method.invokeNative(Native Method) 03-10 11:57:37.000: E/AndroidRuntime(14709): at java.lang.reflect.Method.invoke(Method.java:507) 03-10 11:57:37.000: E/AndroidRuntime(14709): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:849) 03-10 11:57:37.000: E/AndroidRuntime(14709): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:607) 03-10 11:57:37.000: E/AndroidRuntime(14709): at dalvik.system.NativeStart.main(Native Method)

我得到了答案，这是我的 SQLite 选择参数代码

public String Read(String name)
{
    String[] columns = new String[]{SQLiteHelper.COLUMN_NPM, SQLiteHelper.COLUMN_NAME};
    String selection = SQLiteHelper.COLUMN_NAME + " like ? ";
    String[] selectionArgs = {name};
    Cursor cursor = database.query(SQLiteHelper.TABLE_MHS, columns, selection, selectionArgs, null, null, null);


    cursor.moveToFirst();
    String index_name = cursor.getString(cursor.getColumnIndex(SQLiteHelper.COLUMN_NAME));
    String index_npm = cursor.getString(cursor.getColumnIndex(SQLiteHelper.COLUMN_NPM));
    String result = index_npm + " " + index_name;
    return result;
}
4

1 回答 1

1

where 子句是 3d 参数，where args 是第 4 个参数。

您应该执行以下操作：

public String Read(String name)
{
    String[] columns = new String[]{SQLiteHelper.COLUMN_NPM, SQLiteHelper.COLUMN_NAME};
    where = "Name=?";
    String[] whereArgs = new String[]{name};

    Cursor cursor = database.query(SQLiteHelper.TABLE_MHS, columns, where, whereArgs, null, null, null);

    //....
}

查看www.vogella.com/articles/AndroidSQLite/article.html了解详情

于 2013-03-10T04:54:16.167 回答