1. Contents of the database
1. Check it through the "Performance" of the system: Start->Management Tools->Performance (or enter mmc in the run) and then add Add the common SQL statistics (MSSQL General Statistics) to the counter and then select User Connection (User Connection) in the items listed below to query the number of sql server database connections from time to time.
2. Query through system tables: SELECT * FROM [Master].[dbo].[SYSPROCESSES] WHERE [DBID] IN (SELECT [DBID]FROM [Master].[dbo].[SYSDATABASES ] WHERE NAME='databaseName')databaseName is the database that needs to be viewed, and the number of rows queried is the current number of sql server database connections. However, there are some other states that can be used as reference.
Or use the following query statement: select * from sysprocesses where dbid in (select dbid from sysdatabases where name='MyDatabase'). 2. Where can I download the Chinese dictionary database
Chinese Dictionary software file: Software name: Chinese Dictionary Software Language: Simplified Chinese Software category: Domestic software Application platform: win9x/me/nt/2000/xp Download address: . 3. Paradigm
Hello, I am happy to answer your question.
First normal form: ensure atomicity of each column. If each column (or each attribute) is the smallest unit of data that cannot be further divided (also called the smallest atomic unit), it satisfies the first normal form.
For example: Customer table (name, number, address,...) where the "address" column can also be subdivided into countries, provinces, cities, districts, etc. Second normal form: A step further based on the first normal form. The goal is to ensure that every column in the table is related to the primary key.
If a relationship satisfies the first normal form and all other columns except the primary key depend on the primary key, it satisfies the second normal form. For example: in the order table (order number, product number, order date, price,...), "order number" is the primary key, and "product number" has no direct relationship with the primary key column, that is, the "product number" column does not depend on the primary key column. , the column should be deleted.
Third normal form: A step further based on the second normal form. The goal is to ensure that each column is directly related to the primary key column, rather than indirectly. A relationship satisfies third normal form if it satisfies the second normal form and all columns except the primary key do not depend on the primary key column.
In order to understand third normal form, transitive dependency needs to be defined according to one of Armstrong's kilometers. Assume that A, B and C are three attributes of the relationship R. If A->B and B->C, then from these functional dependencies, we can derive A->C. As mentioned above, the dependence on A->C is Transitive dependencies.
For example: order table (order number, order date, customer number, customer name,...). At first glance, there is no problem with the table. It satisfies the second normal form. Each column is consistent with the primary key column "order number". Related, if you look closely you will find that "customer name" is related to "customer number", "customer number" and "order number" are related, and finally through transitive dependency, "customer name" is also related to "order number". In order to satisfy the third normal form, the "Customer Name" column should be removed and placed in the customer table.
4. What words can generally be used to replace database and system?
1. Nowadays, Oracle is mostly used in the general production and manufacturing industry;
2. Sybase is mostly used in commercial enterprises, and Oracle is also used.
3. Most financial management uses sql server (UFIDA, etc.), but now there is also a for oracle version;
4. For small and medium-sized enterprise websites, mysql, There are many sql servers, and most large online shopping malls use orcale.
Oracle and Sybase are both large-scale databases. Generally, the server operating systems that use such databases are Linux; in terms of the security of the operating system, SQL Server will choose Oracle and Sybase for enterprise-level operations. In addition, although mysql also runs on Linux, because it is a free version, it is rarely used at the enterprise level. 5. Can someone please help explain how the database in this article is designed
It must have been designed by SQL Server, because first of all, the amount of data is large and cannot be supported by a stand-alone file database like Access; secondly, SQL Server supports stored procedures, transactions, custom functions, etc., which greatly improves development efficiency and database security. It is also better than access in terms of performance; moreover, a significant feature of sql server is concurrent database connections, while access can only achieve a single connection. In a system with a certain number of user visits, access cannot realize the normal operation of the system at all.
There are many reasons, just briefly mentioned above.
In addition to SQL Server, Oracle is also the backend database of choice for large programs (websites).
Each database has its own management tools, development and debugging environments, external interface protocols, etc. 6. Where can I download the complete idiom dictionary?
The Chinese dictionary contains four classics, thirty-six strategies, 20,901 Chinese characters, 31,000 idioms, 320,000 words, 1,280 sets of synonyms, 5,240 sets of antonyms, There are 93,600 poems, 26,800 riddles, 5,270 couplets, 14,000 sayings, 1,900 sayings, 1,300 proverbs, hundreds of couplet stories, 1,000 children's literature, 1,000 classical Chinese explanations, and many other contents. The function introduction is as follows:
1. The full-text search function can realize fuzzy search based on any content, such as searching for related poems based on words, words, famous sentences, etc.
2. The classification tree is intuitively displayed. Poems, folk sayings, famous sayings, couplets, riddles, articles, etc. are all provided with detailed classification, which can meet the needs of users for leisure reading.
3. Full Chinese computer reading, which can read any Chinese content and convert any text into a sound file;
4. Children's reading aid, which can add pinyin to any text. Note and read aloud, you can also generate a Word file with pinyin annotation. Arbitrary typesetting will not affect the effect, making it more convenient for children to read the article. What needs to be noted in particular is that the pinyin we annotated is the same as the format of the pinyin reading book for children published by the publisher. The same, more in line with children's reading habits, and supports a large number of polyphonic characters, which is essentially different from some that simply add pinyin to the end of Chinese characters.
5. An article manager that supports unlimited categories and is easy to use. It has built-in Chinese classics such as the Four Great Classics, Thirty-Six Stratagems, the complete collection of Aesop's Fables, Andersen's Fairy Tales, One Hundred Chinese Fairy Tales, and Idioms. There are thousands of children's literature works including stories, more than 2,500 wonderful jokes, and a large number of literary works. The added articles can be dragged anywhere in the directory tree to change their classification.
6. A Chinese dictionary, containing 20,901 Chinese characters and their explanations, which can be searched based on Chinese characters, pinyin and radicals;
7. A general dictionary, containing 320,000 words and explanations;
8. An idiom dictionary, including 31,850 idioms, pinyin, definitions, sources and examples, providing interesting idiom solitaire games;
9. A classical Chinese dictionary , including thousands of definitions of classical Chinese words, full-text explanations of classical Chinese texts from junior high school to university, and a large number of ancient Chinese learning skills, all intuitively displayed in the form of a directory tree;
10. A synonym dictionary, including 1280 More than 12 groups of synonyms;
12. An antonym dictionary, including more than 5,240 groups of antonyms;
13. A poetry dictionary, including more than 93,600 poems from pre-Qin to modern times, including the author , appreciation, textual research, etc., intuitively displayed in the form of a directory tree by year and author;
14. A collection of famous sayings and aphorisms, 13,000 famous sayings and their sources, intuitively displayed in the form of a directory tree;
15. A collection of folk sayings, including more than 14,000 idioms, more than 1,900 colloquial sayings, more than 1,300 proverbs and a large number of tongue twisters, intuitively displayed in the form of a directory tree;
16. A collection A collection of riddles, including more than 26,800 riddles, word riddles, poetry riddles, object riddles, etc. and a large number of riddle stories, visually displayed in the form of a directory tree;
17. A collection of couplets, including Spring Festival couplets and birthday couplets , marriage couplets, absolutes, etc. 5270 couplets and hundreds of couplet stories are visually displayed in the form of a directory tree;
18. Perpetual calendar, periodic table of elements, twenty-four solar terms, comparison table of Chinese historical dynasties, world Common tools such as time conversion in various places;
19. Database self-expansion function, you can add content that is not in the database according to your own needs, convenient for daily use;
20. Built-in background music support.
21. With the area code query function, you no longer have to worry about the area code query when filling in various cards.
22. Login provides free online upgrade service.