Because our project is the algorithm class, so the project itself needs less clear. In fact, the database design process itself is in the process further clarify the requirements.
This is our use case diagram drawn:
The following is a database design experience of our team members are:
JJ:
Through this database design process, I experienced a lot also learned a lot.
First, because the required curriculum group is to design at least 15 tables, but we want to achieve 15 table is very difficult. Our idea is to design a prototype based on the design before we first devised some of the tables, according to log in, register, history, and design a few tables. But these tables are also based on the user base is designed, then we also seek the guidance of the teacher's help, to help the instructor thought of a loss function table. But the number of tables is still not enough. Then we went to seek the help of a teacher Geng Yin, Yin under the teacher's help we just like to open a new world.
Before have been trying to add the appropriate function we finally found a way, we have decided not only to write an algorithm. But to compare multiple algorithms, which can increase algorithm table, while training algorithm can also build table. By increasing this table, the function of our project further enriched. As for the situation not really built the table, we can add some additional small auxiliary functions. For example, replace the theme, links and so on. In fact, the table is dependent on the function, a feature-rich, naturally table can be written out.
According to function after completion of construction of the table, we list the main key and type, length, and whether it meets the three basic paradigms are all discussed. The last step determines the basic shape of the table. There are also differences may be here naming different people need unity. Also very grateful to the database on small class lesson given by teacher recommendations put forward some aspects we did not expect, our database table design was perfect.
Learned knowledge and content based software engineering classes, we will apply it to the actual design process, so that the "learning by doing." Database design is to make it later developed to meet the needs, and easy to use as possible, provided on the data type, field constraints such as primary foreign key to more careful consideration of the actual situation.
LUXURY:
Our team do is gesture recognition database project, because it is pure type of algorithm, the very beginning of the table with little effect is not large, then we add the users, and several functions associated with them, so our table finally a little more, and finally we have a better idea by providing help to the teacher, the teacher, and finally to the database generally settle down.
Then we started to improve, we found a lot of problems, such as non-compliance paradigm, variable naming is not uniform, and so on. By setting standards, to discuss, to solve the problem.
Database design part, I think first of all need to figure out the link between the entity (or table), followed by the data type must figure out fields in the table, are char, varchar, int, date & time type and so on, there are a few characters in length. There is whether its value can be empty, which is to be considered. Set Primary Key relatively easier, my greatest experience in the analysis for each column of the table data type must be careful careful, it will be very easy to make mistakes.
Although we learned database, but we still lack experience. Now we use the knowledge he learned to design a database, which in itself is a process of transforming knowledge into productivity, so we are very excited to have invested a high degree of enthusiasm and effort different.
GM:
For a project, the database design is very important, database design determines the future of good data maintenance, demand has not been a good meet, good demand changes to the late start, but also determines the performance of the system. It is not a good database design for a function point changes may involve changes to multiple tables, believe it might lead to inconsistent data. In order to avoid unnecessary trouble, in the beginning of the database design must consider these issues, thereby reducing the latter part of system maintenance. He said that the importance of database design so much, so I have the following thoughts on database design.
About Paradigm and anti paradigm object paradigm designed to reduce data redundancy and thus save memory space to improve search efficiency, but also makes readily available to maintain data consistency. The anti-paradigm design of the main reaction to the examination of the historical data historical issues, we need to redundant data to the table. We must analyze our business which is the case belongs, as the case may be, which way in what way the specific use. As related to the financial aspects related to the future financial reconciliation, there is a great historical change of use, data redundancy is important, it will consider the counter-paradigm. For our project, mainly the need to reduce data redundancy, there was no problem to change history, for the purpose of improving the efficiency of inquiries, we chose the design paradigm
As for the expansion of design, data models early in the project business scenario is one to one, but we project the future a certain degree of vision and analysis of the latter will become many. Do this situation in order to facilitate the initial design data into one model, the latter may do so if Debu loss of taste. This is the expansion of design data need to be considered, not convenient for the moment ignore the extension of the design.
YES:
After the project design prototype design is completed, we carried out the design of the database. The database is to be designed according to the demand, it is our database design experiment requires that we need to know.
When designing a database, we first conduct listed features, and then to design a database containing tables based on those features we want to achieve, what each table contains each field, type field, constraints, and so on. More important is that during the design, taking into account the features of each function to realize the need to use data tables and fields should be carefully designed and reviewed, but also need to consider the complexity of implementation.
Course requirements of each project requires at least a certain amount of design data table, so we focused on this and also the instructor for the communication to discuss needs and finally add some features, making the function of the whole project has been very good fulfilling. Here we started because there are requirements for the number of database tables, so make a lot of data in the table to the table when originally designed. But when later review and integration within the group, it was found it has been designed to put some data together can be separated from the table, so the table is later rearranged.
For determining each table's primary key foreign key, etc., in our opinion there is no group differences. While the tables are designed to meet the paradigm noticed the problem, in line with the specification data table design. The only database designed in line with norms and taking into account the realization of all functions can be regarded as a good database.
QMX:
After completing the needs analysis we followed the completion of the design project database. The last time the feelings and experiences have mentioned, our group project functionality is not too much, mostly concentrated in the user registration and login picture identification here. Therefore, when designing a database, or the emergence of a number of similar problems with the analysis of the needs of the group courses last less than required database tables. At first, the number of tables can think of only less than 10. Later, ask the instructor before they can think of to add to the original data table from another direction, such as the training process of the neural network model, different types of pictures set storage, and so on. Although it pointed out some shortcomings in the private class when the teacher review the details of the table, but in general still cross the border of. Database design our panel discussion, in accordance with the functional requirements of the project to one analysis, such as log-ins may be used in which tables and so on, so that the child can not only improve efficiency, but also to ensure there will be no table or field missing . This discussion in the database design course of other experiments can also learn to use.