在sql db中查找一些项目计数？ [英] Find some item count in sql db ?

问题描述

大家好，我试着在数据库的名字栏中找到john。但我不知道。能否请你帮忙？谢谢..

Hi everybody, I try to find "john" in "name" column in database.But I did't somehow. Could you please help? Thanks..

String st="SELECT name FROM mytable";
ResultSet rs = stmt.executeQuery(st);
int icount = 0 ;
if (rs.equals("john")) {
while (rs.next()) { 
icount++;
}
}
jtext1.setText(String.valueOf(icount));

推荐答案

尝试：

Try:

String st="SELECT name FROM mytable WHERE name LIKE '%john %'";

你可以做到这一切：

You can do it all in one:

String st="SELECT COUNT(*) FROM mytable WHERE name LIKE '%john %'";

String st="SELECT COUNT(*) FROM mytable WHERE name LIKE '%john %'"
ResultSet rs = stmt.executeQuery(st);
int icount = 0;
while (rs.next) {
icount = rs.getInt(1);
}
jtext1.setText(String.valueOf(icount));

上面只有1个记录，其中1个字段是匹配的记录数。



在约翰之后放一个空格以免得到像johnathan等名字，但你可以玩。

There should only be 1 record with 1 field in the above which will be the count of records matching.

Put a space after john so as not to get names like johnathan etc. but you can play around.

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