Is a database a file? What is the format of the database file?

Of course, the status is very high.

Although it is also a file, it has the advantage of storing a large amount of data and is easy to use.

Database file formats include CSV, DAT, DBF, MDB, ODB++, and so on. The details are as follows:

1. CSV is a comma-separated value file format, and its files store ** data in plain text. Plain text means that the file is a sequence of characters and does not contain data that must be interpreted like binary numbers. A CSV file consists of any number of records, separated by some kind of line break; Each record is made up of fields, and the separators between the fields are other characters or strings.

2. DAT file.

DAT files, or data files, are not defined absolutely. The extension of the dat file is. dat。This kind of text is plain text, and there is no information about the structure of the data attributes, and it can be opened with a text tool such as Notepad.

3. DBF is a special file format that represents a database file. Database files generated by database processing systems such as foxbase, dbase, and visual foxpro. Abbreviated as dbf or.

dbase file split, a format created by ashton-tate.

4. MDB The database in MDB format is a relational database. MDB View can read MDB database files without Microsoft Access installed. Because of its convenience for data manipulation, it is commonly used in some small and medium-sized programs.

MDB is the abbreviation of MDB ICP protocol, which is a protocol developed by the European Vending Machine Manufacturers Association to coordinate the communication between the main controller of a vending system and multiple peripherals.

5、odb++

ODB++ is an extensible ASCII format that holds all the engineering data necessary for PCB manufacturing and assembly in a single database. It is a bridge that can connect multiple data format databases, and it is also a bidirectional format that allows data to be transferred up and down.

There are three types of files in the database.

The first type of file is the primary file with a suffix.

For. mdf, the main data in the database is stored in this file, and there is also a file that is a log file with a suffix. LDF mainly records the logs of the database and the operation records of the database.

There must be at least one master file and log file in a database. But there can only be one master file, and the log asks that there can be more than one. There is also a type of file that is a secondary file with the suffix. ldf。It mainly stores some auxiliary information about the database.

Differences in database files:

The database only saves text characters, and the word document we usually use is more commonly used by computer users to check and use, and the database information is only frequently used in computer software development, and general users do not need to open it. The content of the database is also very important, so it is best not to delete it at will.

File system. The files in the database are only the files that support the database to run, and the file storage structure of the database files is a regular cluster and some professional database systems.

Contiguous space is reserved for database files to improve indexing speed (oracle.

It's just a different location, of course, the key files are different for them, the database is used for **, and the former system is the system file to be called when it is operating normally.

Files with the suffix MDF are data copy, that is, the number that stores you.

According to the table and the data inside the file, while. LDF and NDF files store your log files, as well as for each operation you take on the database and when, so that you can resume the previous operation if you make a mistake.

.MDF is the main file of the database.

ldf is the log file of the database.

MDF is the database file and LDF is the log file.

1) Master file. A master file is a persistent data resource for a specific application. The master file contains those records that are accessed periodically to provide information and are frequently updated to reflect the latest status.

Typical main documents include inventory documents, employee master documents and accounts collection master documents.

2) Transaction documents. Transaction files contain those records of data activities (transactions) that act as an information system. These transactions are batched to form transaction files.

For example, a number of recorded items from a weekly payroll card are stored in batches on a transactional file and then processed against a payroll file to print out paycheck and payroll register.

3) Table file. Table files are some**. The reason why the table file is created separately and not designed in the program is to facilitate modification. For example, a utility company's tax rate table or the IRS tax rate can be stored in Chinese form.

4) Alternate documents. An alternate file is a replica of an existing production document. Once a productive file has been compromised, the production file can be re-established using a spare file.

5) Archival documents. Archival documents are not provided for current processing, but are preserved as historical references. For example, the Internal Revenue Service (IRS) may require an inspection of a person's last 15 years.

In fact, an archival file is precisely the one that works in a given time"Snapshots"。

6) Output file. The output file contains a numerical image of the information that will be printed on the printer, displayed on the screen, or plotted on the plotter. The output file can be:"Spooled"(stored on a secondary memory device) when the output device is available.

The actual output is carried out only when the front is raised.

The most commonly used database files.

AESS database and MySQL

For small businesses and ** use.

Basically, the role is to record statistics, and the general common file is used for executable files.

folders, such as exes

Wait. Many, many files.

However, when asking this question, it is recommended that you first go to the ** to find the information and see.

They are very different! Reversal and this question is very extensive, and there is no accurate answer.

Extension, full name file suffix.

Common graphics file format suffixes: BMP, DIB, PCP, DIF, WMF, GIF, JPG, TIF, EPS, PSD, CDR, IFF, TGA, PCD, MPT, and PNG.

The images that are captured (e.g., shots, screenshots) are pixel maps. Pixel maps will be blurry when they are bolded to a certain extent. Common pixel map formats include:

jpeg、psd、png、tiff。

Vector illustration: is an image composed of points, lines, and surfaces. Vector graphics are often drawn using vector software. Points, lines, and surfaces are all mathematical, because.

Common database file formats are as follows:

1. CSV comma-separated value file; DAT data files; wrodperfect merge data files; Paradox 7 table of DB Borland; DBC Microsoft Visual FoxPro database container file.

2. In addition, there are many database files defined by software developers themselves, most of which use DAT, or convert DBA to DAT, and convert the program file name to process.

3. ODB++ is an extensible ASCII format, which can save all the engineering data necessary for PCB manufacturing and assembly in a single database. It is a bridge that can connect multiple data format databases, and is a bidirectional format that allows data to be transferred up and down.

The main difference between a database and a data fileThe database contains several files, and the links between the records are realized by linking the road backup paths;

Databases can reflect the connections and meanings of information in the display world;

The file contains only the data itself, while the database contains the basic data and data about the data, such as data that reflects connections, reflects semantics, and is attached for management control.