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12,721 PointsWhy "%s=%s" in the String.format(..) method?
In this video, why has Evan Anger used the format "%s=%s" for ID values where an additional data type conversion was required (from int to String) instead of using the format "%s=%d" like in the previous cases?
1 Answer
Harry James
14,780 PointsI believe Evan was just showing an alternate method of doing this.
If you were to change your code to
database.delete(MemeSQLiteHelper.ANNOTATIONS_TABLE,
String.format("%s=%d", MemeSQLiteHelper.COLUMN_FOREIGN_KEY_MEME,
memeId), null);
database.delete(MemeSQLiteHelper.MEMES_TABLE,
String.format("%s=%d", BaseColumns._ID,
memeId), null);
then it would also work fine.
However, this would not work:
// ** ** ** This would cause an error because the second parameter is not a String (%s) ** ** **
database.delete(MemeSQLiteHelper.ANNOTATIONS_TABLE,
String.format("%s=%s", MemeSQLiteHelper.COLUMN_FOREIGN_KEY_MEME,
memeId), null);
database.delete(MemeSQLiteHelper.MEMES_TABLE,
String.format("%s=%s", BaseColumns._ID,
memeId), null);
or this:
// ** ** ** This would cause an error because the second parameter is not a integer/decimal (%d) ** ** **
database.delete(MemeSQLiteHelper.ANNOTATIONS_TABLE,
String.format("%s=%d", MemeSQLiteHelper.COLUMN_FOREIGN_KEY_MEME,
String.valueOf(memeId)), null);
database.delete(MemeSQLiteHelper.MEMES_TABLE,
String.format("%s=%d", BaseColumns._ID,
String.valueOf(memeId)), null);
I can understand the confusion this could cause but, as long as you understand that the formatters have to match the parameters, it doesn't matter what you put :)