Problem a: just don't work, the company a lot of code headache, who only need a table in the database of individual fields, have to find out the whole entity class to come out, it will not affect the efficiency of the query?

Question 2: the company of some of the data is preserved by level table, such as according to the points in time, then I need to cross table query, for example to deal with the date of the coming I like write the service layer, and then the heads of the original ready to write good, let me with the data before writing the code finds out I need less than 5 seconds, written in the original JDBC inside the dense, equally large amount of data, with more than 1 minute, anyway, very slowly, so good?

CodePudding user response:

As group leader, said can't throwing

CodePudding user response:

Problem a: you're right, according to your
Problem two: leader's right, listening to the group leader

CodePudding user response:

Problem a: use the entity data to map database table, this is the normal operation, although you are worried about performance problems, but the years of experience tells us that this performance sacrifice is worth it,
Question 2: if the customer not strong performance requirements, the boss will not care about performance issues (don't want you to waste time here), a big deal to write a set of, this is the common fault of the small company boss,

CodePudding user response:

reference response: 1/f friendship dream

with leader said, not throwing

listen to the group

CodePudding user response:

refer to the second floor KeepSayingNo response:

problem a: you're right, according to your
Problem two: leader's right, listening to the group leader of

listen to the team long

CodePudding user response:

reference datafansbj reply: 3/f

problem a: use the entity data to map database table, this is the normal operation, although you are worried about performance problems, but the years of experience tells us that sacrifice is worth this performance,
Question 2: if the customer not strong performance requirements, the boss will not care about performance issues (don't want you to waste time here), a big deal to write a set of, this is the common fault of the small company boss,

company also not small, several hundred people, doing no project performance requirements are true

CodePudding user response:

Unless the export data, query entity and there is not much problem, otherwise the jpa that things are not so popular.
Table performance difference there should be a way to solve this..

CodePudding user response:

Problem a, for the general project is not the problem, unless it is large amount of data, and just check index of field is the field, or check a field and multiple fields difference is not big, after all, network transmission bandwidth is not a problem.
Problem two, listen to the team, after a time tested is appropriate, can carry their optimization scheme, after evaluation can confirm confirm adopted,

CodePudding user response:

refer to the eighth floor. Kevin Y.K response:

a problem, is not a problem for the general project, unless it is large amount of data, and just check index of field is the field, or check a field and multiple fields difference is not big, after all, the network transmission bandwidth is not a problem.
Problem two, listen to the team, after a time tested is appropriate, can carry their optimization scheme, after evaluation can confirm confirm adopted,

indeed, my SQL may some strange bugs, such as the learned