A summary of the database

I watched several more sets of videos. The knowledge of databases is also deeper. In fact, it is like dealing with people. It is natural that you will be familiar with it after a long period of time. This idea is also a way to learn technology. After reading a few sets of videos, I think some places (Data Query and filtering) are similar to the previous access, and some places (T-

I watched several more sets of videos. The knowledge of databases is also deeper. In fact, it is like dealing with people. It is natural that you will be familiar with it after a long period of time. This idea is also a way to learn technology. After reading a few sets of videos, I think some places (Data Query and filtering) are similar to the previous access, and some places (T-

I watched several more sets of videos. The knowledge of databases is also deeper. In fact, it is like dealing with people. It is natural that you will be familiar with it after a long period of time. This idea is also a way to learn technology.

After reading a few sets of videos, I think some places (Data Query and filtering) are similar to the previous access. Some places (T-SQL) and vb (or other programming languages) very similar. The concept of a cursor is introduced. It is like placing a small truck in the warehouse. Some data can be placed in the cursor for processing. The cursor allows operations on each row. Based on the row content, you can determine the next action to be taken. However, the cursor occupies a large amount of resources, so you should release the cursor (close) in time when you are sure not to use the cursor ). In addition, the use of cursors is often the final method, rather than the first choice. There are also a series of operations on the cursor. The next step is transaction management. This part is unique to the database (compared with the previously learned vb). It is introduced to ensure data security, when an accident occurs, the corresponding handling method is provided, which is atomic, that is, the Operation integrity. The lock concept will be mentioned later. The introduction of the lock aims at data security and sets the data access permissions. There are also a series of concepts about the lock. This should have been the introduction of concepts before. From the next set of videos-creating databases, we can infer that these concepts will be applied in the future.

Late at night, sleeping.