nosql database types with example

The field type in the database corresponds to the data type in C #: Database C # programint int32Text stringbigint Int64Binary system.byte[]Bit BooleanChar stringDateTime System.DateTimeDecimal System.DecimalFloat System.DoubleImage system.byte[]Money System.DecimalNCHAR Stringntext StringNumeric System.Decimalnvarchar StringReal System.Singlesmalldatetime System.DateTimesmallint Int16SmallMoney System.Deci

QT provides a qtsql module to provide platform-independent SQL-based database operations. What we call "platform independence" here includes both the operating system platform and the various database platforms. In addition, we emphasize "SQL-based" because NoSQL databases do not have a common query method so far, so it is impossible to provide a generic

Types and Research of Oracle Database locks, oracle Database locks A database is a shared resource used by multiple users. When multiple users access data concurrently, multiple transactions can access the same data simultaneously in the database. If concurrent operations a

personally at the end of the third category, so some of the design skills listed below are only applicable to the second and some third-category database designers. At the same time, as I rarely encounter colleagues who are interested in drilling down in this area, it is inevitable that errors and omissions will appear in this article. I would like to make a statement first. You are welcome to correct it and do not hide it in private. 8) 1. Data Tabl

Django is an open source model-View-Controller (MVC)-style WEB application framework that is driven by the Python programming language. With Django, we can create high-quality, maintainable, database-driven applications within minutes. Now let's take a look at how you can use the database in Django:Common data Types Autofield: int self-added, parameters must be p

WordPress set Post Type custom article types example tutorial, wordpress instance Tutorial What is a custom post?Don't take it for granted that the post here is just a blog post, it's just a surrogate word for an article class, and you can even think of it as content.Custom model is not a very standard what rules, the article model can be any one of the content model you want, take WordPress itself is buil

uniqueidentifier.The Timestamp is used to represent the sequence of SQL Server activities in a binary projection format. Timestamp data is not related to inserting data or date and time.The Bit is made up of 1 or 0. When representing true or false, on, or off, use the Bit data type. For example, ask if a client request for each visit can be stored in a column of this data type.The uniqueidentifier consists of 16-byte hexadecimal digits that represent

Tags: bin time interval Basic date values today knowledge three times simplePreface Today go to fitness, feel the body practice good or good, gossip not to say, the data types encountered in this database today all here to speak clearly, after seeing what data type, I should know, for me, the most unfamiliar should be the time type this piece. But through today's study, has already doubts. Just follow my rh

Tags: resource management CTI based on value type currency line data amp oba secondsA data type is an attribute that specifies the type of data that an object can hold, and supports multiple data types in SQL Server, including character types, numeric types, and date types. The data type is equivalent to a container, t

In many applications, although the general use of a database operation, but due to the needs of various situations, the business system may be deployed in different types of databases, if the development of the system can easily support a variety of database switching, it can reduce the number of problems for us, while improving the adaptability and robustness of

?? A data type is an attribute that specifies the type of data that an object can hold, and supports multiple data types in SQL Server, including character types, numeric types, and date types. The data type is equivalent to a container, the size of the container determines how many things are loaded, and dividing the

inserted string is lower than the upper limit, the system automatically reduces it to the true length of the string. Number (m, n): Can be used to represent both integer and floating point types. However, m cannot exceed 38. If n is 0 or n is omitted, it indicates that it is an integer. Date: used to store the date and time Blob: it is usually used in applications, rather than directly using SQL commands in databases. For

fields, the precision requirement is not high. Of course, FLOAT is used. But to be honest, how can we use the MySQL Data Type of "civil", which requires a high accuracy? I have never used these two types-I have not encountered any examples that are suitable for using them. The most commonly used, most cost-effective, is the integer type. From TINYINT, which occupies only one byte of storage space, to BIGINT, which occupies eight bytes, selecting a ty

storage space, to BIGINT, which occupies eight bytes, selecting a type that is "adequate" and occupies the smallest storage space should be considered during database design. The storage space occupied by TINYINT, SMALLINT, MEDIUMINT, INT, and BIGINT is 1 byte, 2 byte, 3 byte, 4 byte, and 8 byte, respectively. For unsigned integers, the maximum Integers of these types are 255, 65535, 16777215, 4294967295,

space, to BIGINT, which occupies eight bytes, selecting a type that is "adequate" and occupies the smallest storage space should be considered during database design. The storage space occupied by TINYINT, SMALLINT, MEDIUMINT, INT, and BIGINT is 1 byte, 2 byte, 3 byte, 4 byte, and 8 byte, respectively. For unsigned integers, the maximum Integers of these types are 255, 65535, 16777215, 4294967295, and 1844

4 bytes and 8 bytes respectively. If you need to use decimal fields, the precision requirement is not high. Of course, FLOAT is used. But to be honest, how does our "Civil" data require high accuracy? I have never used these two types-I have not encountered any examples that are suitable for using them. The most commonly used, most cost-effective, is the integer type. From TINYINT, which occupies only one byte of storage space, to BIGINT, which occup

mode It is troublesome to input data one by one. We can add all records to your database table using text files. Create an example file named "“mysql.txt". Each line contains a record. Use a tab to separate the values and give them in the order of the columns listed in the create table statement. For example: abccs f 1977-07-07 china 　 m

Main Oracle Data Types Overview: The data types supported by various databases are similar to those in standard SQL languages. Type: varchar2: You can set the maximum length of a field when declaring it. After using it, you do not have to consider the existence of spaces. If the length of the inserted string is lower than the upper limit, the system automatically reduces it to the true length of the string.

byte, 3 byte, 4 byte, and 8 byte, respectively. For unsigned integers, the maximum Integers of these types are 255, 65535, 16777215, 4294967295, and 18446744073709551615. If it is used to save the user's age (for example, it is not advisable to store the age in the database), TINYINT is enough. In 9-city's vertical bar, skill values, SMALLINT is enough. If you w

. The storage space occupied by FLOAT and DOUBLE types is 4 bytes and 8 bytes respectively. If you need to use decimal fields, the precision is not high, of course, FLOAT is used! But to be honest, how does our "Civil" data require high accuracy? I have never used these two types so far-I have not encountered any examples that are suitable for using them.The most commonly used, most cost-effective, is the i