如何实现androidsqlite查询?
我正在使用以下代码搜索“English”列。还有一个专栏叫“孟加拉语”。我应该如何修改代码,以便同时搜索“ENGLISH”和“BANGLA”列并作为组合结果返回如何实现androidsqlite查询?,android,sqlite,Android,Sqlite,我正在使用以下代码搜索“English”列。还有一个专栏叫“孟加拉语”。我应该如何修改代码,以便同时搜索“ENGLISH”和“BANGLA”列并作为组合结果返回 public List<Bean> getWords(String englishWord) { if(englishWord.equals("")) return new ArrayList<Bean>(); String sql = "SELECT *
public List<Bean> getWords(String englishWord) {
if(englishWord.equals(""))
return new ArrayList<Bean>();
String sql = "SELECT * FROM " + TABLE_NAME +
" WHERE " + ENGLISH + " LIKE ? ORDER BY " + ENGLISH + " LIMIT 100 ";
SQLiteDatabase db = initializer.getReadableDatabase();
Cursor cursor = null;
try {
cursor = db.rawQuery(sql, new String[]{"%" + englishWord + "%"});
List<Bean> wordList = new ArrayList<Bean>();
while(cursor.moveToNext()) {
int id = cursor.getInt(0);
String english = cursor.getString(1);
String bangla = cursor.getString(2);
String status = cursor.getString(3);
wordList.add(new Bean(id, english, bangla, status));
}
return wordList;
} catch (SQLiteException exception) {
exception.printStackTrace();
return null;
} finally {
if (cursor != null)
cursor.close();
}
}
然而,这是行不通的。我得到这个错误:
ORDER BY clause should come after UNION ALL not before (code 1): , while compiling: SELECT * FROM words WHERE en_word LIKE ? ORDER BY en_word LIMIT 100 UNION ALL SELECT * FROM words WHERE bn_word LIKE ? ORDER BY en_word LIMIT 100
您需要按如下方式移动订单并将其限制到末尾:
SELECT * FROM TABLE_NAME
WHERE ENGLISH LIKE ?
UNION ALL
SELECT * FROM tull
WHERE BANGLA LIKE ?
ORDER BY ENGLISH LIMIT 100
但是,这将只按英文订购,最多100行。每种语言需要100行吗?如果要按这两种语言排序,可以为列添加别名,并按该别名排序:
SELECT *, ENGLISH AS TEXT FROM tull
WHERE ENGLISH LIKE ? OR BANGLA LIKE ?
UNION ALL
SELECT *, BANGLA AS TEXT FROM tull
WHERE BANGLA LIKE ""
ORDER BY TEXT LIMIT 100;
您仍然需要添加第二个selection参数,如注释中提到的jyanks。这与中的不一样。您得到的确切错误是什么?可能你没有添加第二个选择参数吗
cursor=db.rawQuery(sql,新字符串[]{“%””+englishWord+“%”,“%””+englishWord+“%”})代码>我正在获取我正在获取wordList==null
。我按照建议添加了第二个selection参数,但仍然不起作用。错误是,orderby子句应该出现在UNION之后,而不是前面(code 1)
谢谢。这解决了我的问题。
SELECT *, ENGLISH AS TEXT FROM tull
WHERE ENGLISH LIKE ? OR BANGLA LIKE ?
UNION ALL
SELECT *, BANGLA AS TEXT FROM tull
WHERE BANGLA LIKE ""
ORDER BY TEXT LIMIT 100;