Mysql data types

This chapter provides an overview and more detailed description of the properties of the types in each category, and a summary of the data type storage requirements. You should use only the type and size of field. A data type specifies a particular type of data , such as integer, floating-point, Boolean etc.

A data type also specifies the possible values for that type , the operations that can be performed on that type and the way the values of that type are stored. Out-of-Range and Overflow Handling”. Data Type Storage Requirements”. Sometimes, data can have only a limited number of values.

For example, the only possible values for a column might be yes or no. The numeric data types include Integer, Fixed-Point, Floating-Point, and Bit-Value. Refer to the following table. MySQL numeric data types. This article provides details of these data types.

We often use the DECIMAL data type for monetary data such as prices, salary, account balances, etc. If you design a database that handle the monetary data , the following syntax should be OK. It also identifies the possible values for that type , the operations that can be performed on that type and the way the values of that type are stored.

A DATE data type can store only date part, it will not store time. If there is a length defined for the destination data type then the maximum value of the two lengths is taken. As a programmer, understanding the data types is curial in understanding the working of the underlying database system. SQL data types can be broadly divided into following categories. Date and Time data types such as Date , Time, Datetime etc.

Character and String data types such as char, varchar, text etc. Unicode character string data types , for example nchar, nvarchar, ntext etc. However, it uses TINYINT(1) instead. To determine which data types a driver supports, an application calls SQLGetTypeInfo.

SQL supports three sorts of data types : predefined data types , constructed types , and user-defined types. Predefined data types are sometimes called the built-in data types , though not in this International Standard. Every predefined data type is a subtype of itself and of no other data types.

These types are used when it is important to preserve exact precision, for example with monetary data. The arguments are identical, but the field type is returned instead. Using these functions, we can convert geometries into WKT, WKB and JSON formats (and vice-versa). When you need a string data type column to only store allowable values from a preferred list, this is one area where an ENUM is a strong candidate. The advantage of storing it as string data is that numeric datatypes will strip off leading zeros, remove spaces, etc.

Comments 참고 : The DATE , DATETIME, and TIMESTAMP Types mysql 테이블 생성시 DATE. I want to get the column data type of a mysql table. Thought I could use MYSQLFIELD structure but it was enumerated field types.

Then I tried with mysql _real_query.