Question

我需要从数据库中选择所有以字母开头的名字，但没有字母＆＃34; x＆＃34;。

对于现在存在于以下代码中的一些标题（它很慢但它有效）：

 String qstr = "SELECT SUM("+SQLhelper.COL_COUNT +") FROM " 
               + SQLhelper.TABLE_MYDETAILS + " WHERE " +        
                         SQLhelper.COL_DETAILID + " LIKE 'sh%'" + 
                " or " + SQLhelper.COL_DETAILID + " LIKE 'sw%'" +
                " or " + SQLhelper.COL_DETAILID + " LIKE 'cty%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'twn%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'tlm%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'sp%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'rac%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'frnd%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'elf%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'pm%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'cas%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'oct%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'hp%'"+    
                " or " + SQLhelper.COL_DETAILID + " LIKE 'njo%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'loc%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'stu%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'iaj%'"+ 
                " or " + SQLhelper.COL_DETAILID + " LIKE 'tlr%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'lor%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'ovr%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'tnt%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'pi%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'idea%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'min%'"+
                " or " + SQLhelper.COL_DETAILID + " LIKE 'trn%'"; 
    Cursor allc = db.rawQuery(qstr, null);          
    allc.moveToFirst();        
    int cnt = allc.getInt(0);
    if(cnt==0) {
        Toast.makeText(this, getResources().getString( R.string.myminifigsnotfound ), Toast.LENGTH_LONG).show();
        return;
    }
    allc.close();

当我添加其他名称时必须添加到查询字符串中。我尝试使用正则表达式：

 sql = "SELECT " + SQLhelper.COL_DETAILID + "," + SQLhelper.COL_COUNT 
      + " FROM " + SQLhelper.TABLE_INSTRUCTIONS 
     + " where " +SQLhelper.TABLE_INSTRUCTIONS_SETID + "="+setid 
       + " and "+ SQLhelper.COL_DETAILID +" LIKE '[a-wyz]%'";

但它不起作用，它返回一个空查询。怎么做？

Answer 1

回答这个问题可能有点晚了，但是我把它放在那些可能会在以后面临同样问题的人身上。要在Android的Sqlite中使用REGEXP运算符，您可以使用库SqliteRE：

https://github.com/mobi-life/sqlitere

如果需要，它还支持加密数据的可选功能。

Answer 2

据我所知，正则表达式（REGEXP）是Android上SQLite不支持的少数几项内容之一。只有一些占位符适用于LIKE，这些占位符为%和_。

您可以做的是，转而查询：

SELECT SUM("+SQLhelper.COL_COUNT +")
  FROM SQLhelper.TABLE_MYDETAILS
 WHERE INSTR ('sh|sw|...',   SUBSTR(SQLhelper.COL_DETAILID, 1, 2)) > 0
    OR INSTR ('cty|twn|...', SUBSTR(SQLhelper.COL_DETAILID, 1, 3)) > 0;

android sqlite和正则表达式

2 个答案: