I am writing something for my friend that will involve storing some data in a database with a primary key which is an integer which will increment. For example:
我正在为我的朋友写一些东西,其中涉及将一些数据存储在数据库中,主键是一个将增加的整数。例如:
id name Age
1 James 15
2 Max 24
3 Jordan 61
How would I retrieve the integer under the id column in the last row? And this would be with Java. Thanks.
如何在最后一行的id列下检索整数?这将是Java。谢谢。
2 个解决方案
#1
2
If the "last" row is the one with the highest ID, your SQL (to retrieve just the ID, like you asked) will look like:
如果“最后”行是具有最高ID的行,则您的SQL(仅检索ID,就像您要求的那样)将如下所示:
SELECT id FROM User ORDER BY id DESC LIMIT 1;
In Java, you'll probably be using JDBC; best practice is to learn how to use PreparedStatement
s.
在Java中,您可能正在使用JDBC;最佳实践是学习如何使用PreparedStatements。
#2
0
is it like
是这样的
id name age
id名称年龄
1 james 15
2 max 24
3 jordan 61
PRIMARY KEY(id)
SELECT id
FROM `tablename`
ORDER BY id DESC
LIMIT 0 , 1
this will return the last row id result set from ur table
这将从ur表返回最后一行id结果集
#1
2
If the "last" row is the one with the highest ID, your SQL (to retrieve just the ID, like you asked) will look like:
如果“最后”行是具有最高ID的行,则您的SQL(仅检索ID,就像您要求的那样)将如下所示:
SELECT id FROM User ORDER BY id DESC LIMIT 1;
In Java, you'll probably be using JDBC; best practice is to learn how to use PreparedStatement
s.
在Java中,您可能正在使用JDBC;最佳实践是学习如何使用PreparedStatements。
#2
0
is it like
是这样的
id name age
id名称年龄
1 james 15
2 max 24
3 jordan 61
PRIMARY KEY(id)
SELECT id
FROM `tablename`
ORDER BY id DESC
LIMIT 0 , 1
this will return the last row id result set from ur table
这将从ur表返回最后一行id结果集