安卓 sqlite更新最后一个插入行

Question

I want to update the last inserted row, but I get an error:

08-20 12:08:23.091: E/AndroidRuntime(13598): android.database.sqlite.SQLiteException: near "ORDER": syntax error (code 1): , while compiling: UPDATE REVIEW SET json=? WHERE ORDER BY date DESC LIMIT 1

My code:

public int updateDataJSON(Review review) {
    SQLiteDatabase db = this.getWritableDatabase();

    ContentValues values = new ContentValues();
    values.put(KEY_JSON, review.getJson());

    return db.update(TABLE_REVIEW, values, " ORDER BY date DESC LIMIT 1", null);
}

Answer 1

ORDER BY and such are only valid in SELECT queries, not UPDATE s.

Consider the following:

1. Store the last inserted row id as returned by a call to insert() :

    long lastInsertRowId = db.insert(...); 

2. Use the rowid in the update like

    db.update(TABLE_REVIEW, values, "ROWID=?", new String[] { String.valueOf(lastInsertRowId)2 }); 

Answer 2

You have to read the last date in a separate step:

db.update(..., "date = (SELECT max(date) FROM ReviewTable)", ...);

(If there are multiple rows with the same date value, this will update all of them.)