android rawquery和query的比較

android rawquery和query的比較
Cursor cursor = db.rawQuery("select name from *** where id=?", new String[]{"1"});
Cursor cursor = db.query("***", new String[]{"name"}, "id=?", new String[]{"1"}, null, null, null);

上面是兩個分別是query和rawQuery的查詢語句，主要區別是rawQuery是直接使用SQL語句進行查詢的，也就是第一個參數字串，在字串內的“？”會被後面的String[]數組逐一對換掉；而query函數是Android自己封裝的查詢API：它的API文檔如下：
public Cursor query (String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy)

Query the given table, returning a Cursor over the result set.

table
The table name to compile the query against.

columns
A list of which columns to return. Passing null will return all columns, which is discouraged to prevent reading data from storage that isn't going to be used.

selection
A filter declaring which rows to return, formatted as an SQL WHERE clause (excluding the WHERE itself). Passing null will return all rows for the given table.

selectionArgs
You may include ?s in selection, which will be replaced by the values from selectionArgs, in order that they appear in the selection. The values will be bound as Strings.

groupBy
A filter declaring how to group rows, formatted as an SQL GROUP BY clause (excluding the GROUP BY itself). Passing null will cause the rows to not be grouped.

having
A filter declare which row groups to include in the cursor, if row grouping is being used, formatted as an SQL HAVING clause (excluding the HAVING itself). Passing null will cause all row groups to be included, and is required when row grouping is not being used.

orderBy
How to order the rows, formatted as an SQL ORDER BY clause (excluding the ORDER BY itself). Passing null will use the default sort order, which may be unordered.


Returns
?A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details.

而後者query對比前者來講就有一個好處，前者rawQuery你在寫入SQL語句的時候，有可能寫錯了或者寫漏了什麼單詞拼字錯誤的時候他會出錯，而後者相對來講出錯的機率就比較小