Question

这是我的表格设置：

public static final String TABLE_DEBT = "debt";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_DEBT_NAME = "debt_name";
public static final String COLUMN_DEBT_TOTAL = "debt_total";
public static final String COLUMN_APR = "apr";
public static final String COLUMN_PAYMENT = "payment";
public static final String COLUMN_SPECIAL_RATE = "s_rate";
public static final String COLUMN_SPECIAL_TIME = "s_time";
public static final String COLUMN_FIRST_FEE = "first_apr_fee";
public static final String COLUMN_PAY_DATE = "pay_date";
private static final String DATABASE_NAME = "debt.db";
private static final int DATABASE_VERSION = 1;


private static final String DATABASE_CREATE = "create table " + TABLE_DEBT + "( " + COLUMN_ID + " integer primary key autoincrement, " + COLUMN_DEBT_NAME + " text not null, " + COLUMN_DEBT_TOTAL
            + " text not null, " + COLUMN_APR + " text not null, " + COLUMN_PAYMENT + " text not null, " + COLUMN_SPECIAL_RATE + " text, " + COLUMN_SPECIAL_TIME + " text, " + COLUMN_FIRST_FEE + " text, " + COLUMN_PAY_DATE + " text)";

我正在使用这种条件格式的查询来按用户选择进行排序：

    if (DebtPlanner.PlanType.equals("highint")) {
         c = database.rawQuery("SELECT *  FROM debt ORDER BY apr DESC;", null);
         Log.d("TAG", "DebtPlanner.PlanType is " + DebtPlanner.PlanType);
    } else if (DebtPlanner.PlanType.equals("lowbal")) {
         c = database.rawQuery("SELECT *  FROM debt ORDER BY debt_total ASC;", null);
         Log.d("TAG", "DebtPlanner.PlanType is " + DebtPlanner.PlanType);
    } else if (DebtPlanner.PlanType.equals("highbal")) {
         c = database.rawQuery("SELECT *  FROM debt ORDER BY debt_total DESC;", null);
         Log.d("TAG", "DebtPlanner.PlanType is " + DebtPlanner.PlanType);
    }

已添加代码：

for (c.moveToFirst(); !c.isAfterLast(); c.moveToNext()) {
            indName[j++] = c.getString(c.getColumnIndex("debt_name"));
            indBal[k++] = c.getDouble(c.getColumnIndex("debt_total"));
            indPay[l++] = c.getDouble(c.getColumnIndex("payment"));
            indApr[m++] = c.getDouble(c.getColumnIndex("apr"));
            indSRate[e++] = c.getString(c.getColumnIndex("s_rate"));
            indSTime[f++] = c.getInt(c.getColumnIndex("s_time"));
            indDay[d++] = c.getString(c.getColumnIndex("pay_date"));

            rowCounter[n++] = n;
        }


    for (int i : rowCounter) { 

       nameList.add(indName[r++]); // This is the name of each debt that shows out of order.
       // lots of edited calucaltion here

     }

然而，他们排序，但不是按预期值排序。例如，当我说按debt_toal（ASC或DESC）排序时，它按debt_name排序（它使ASC或DESC部分正确）。

我查看了手机中的实际表格，所有数据都在正确的列中。我甚至不确定从哪里开始？

额外代码：

public class DebtPlanner extends Application {

    public static String PlanType = "highint";


    public static String highIntPlan() {
        return DebtPlanner.PlanType = "highint";
    }

    public static String lowBalPlan() {
        return DebtPlanner.PlanType = "lowbal";
    }

    public static String highBalPlan() {
        return DebtPlanner.PlanType = "highbal";
    }

}

Answer 1

比较Java中的字符串时，必须使用equals()，而不是==：

if (DebtPlanner.PlanType.equals("default")) {

How do I compare strings in Java?

对此有很好的解释

此外，您应该在后续查询中使用else if，因为它们是相互排斥的想法。

它一直在正确排序。问题是，列是String。所以，从技术上讲，2大于1000000.现在我只需要弄清楚如何纠正这个......

好的，使用CAST将列排序为整数而不是文本：

SELECT * FROM debt ORDER BY CAST(apr AS INTEGER) DESC;

Answer 2

使用

Log.d("TAG", "DebtPlanner.PlanType is " + DebtPlanner.PlanType);

确保您的多个if

中包含正确的数据

SQlite查询按错误列排序

2 个答案: