What is the default value of ENUM?
value 0
It is whatever member of the enumeration represents the value 0 . Specifically, from the documentation: The default value of an enum E is the value produced by the expression (E)0 . Without overriding the default values, printing default(E) returns Foo since it’s the first-occurring element.
What is MySQL default value?
0
For numeric types, the default is 0 , with the exception that for integer or floating-point types declared with the AUTO_INCREMENT attribute, the default is the next value in the sequence. For date and time types other than TIMESTAMP , the default is the appropriate “zero” value for the type.
What is enumeration value?
An enumeration is a data type that consists of a set of named values that represent integral constants, known as enumeration constants. An enumeration is also referred to as an enumerated type because you must list (enumerate) each of the values in creating a name for each of them.
What is ENUM data type in MySQL?
An ENUM is a string object with a value chosen from a list of permitted values that are enumerated explicitly in the column specification at table creation time.
What is enumeration in C# with example?
In C#, an enum (or enumeration type) is used to assign constant names to a group of numeric integer values. It makes constant values more readable, for example, WeekDays. Monday is more readable then number 0 when referring to the day in a week.
What is default of enum C#?
The default value for an enum is zero.
What is the default value of varchar in MySQL?
NULL is the actual NULL value meaning if no value is provided on an insert the column will default to NULL (empty). For varchar you can set default to ”, but NULL is better. Autoincrement int types shouldn’t have a default value (Default: None) because it will always have a value.
How do I select default value in SQL?
Select the column for which you want to specify a default value. In the Column Properties tab, enter the new default value in the Default Value or Binding property. To enter a numeric default value, enter the number.
Why do we use enumeration?
Enumerations make for clearer and more readable code, particularly when meaningful names are used. The benefits of using enumerations include: Reduces errors caused by transposing or mistyping numbers. Makes it easy to change values in the future.
What is an example of enumeration?
To enumerate is defined as to mention things one by one or to make clear the number of things. An example of enumerate is when you list all of an author’s works one by one. To count off or name one by one; list. A spokesperson enumerated the strikers’ demands.
What is enumeration in database?
Enum, short for “enumerated,” is a data type that consists of predefined values. A constant or variable defined as an enum can store one of the values listed in the enum declaration. Enums provide a highly structured way to store data since they can only store a single pre-defined value.
What is the difference between ENUM and set in MySQL?
Difference between SET and ENUM. The difference between SET and ENUM is that SET column can contain multiple values and whereas an ENUM can hold only one of the possible values. The SET type is similar to ENUM whereas the SET type is stored as a full value rather than an index of a value as with ENUM.
How can I insert default value in MySQL enum data type?
We can do it with the help of the DEFAULT attribute of the ENUM data type. The DEFAULT attribute causes an ENUM data type to have a default value when a value is not specified.
How are enumeration values sorted in MySQL?
MySQL sorts the enumeration values based on their numeric indexes that depend on the order in which we have inserted the data in the column specification. For example, if we have defined the enumeration as ENUM (‘b’, ‘a’, ”, ‘c’).
When to use not null in MySQL enum?
NOT NULL: By default, the ENUM data type is NULL. If we do not want to allow the NULL values, it is required to use the NOT NULL property while specifying the ENUM column. NULL: It is a synonym for DEFAULT NULL, and its index value is always NULL. DEFAULT: When a value is not specified in the column, the ENUM data type inserts the default value.
How to assign priority to enum in MySQL?
Suppose, we want to store the student data in the table Student_grade in order to store the grades of students in the corresponding columns (High, Medium, Low). We use the priority statement to assign the priority to the Enum column. The prioritized column will accept only three columns. Here, the order of numbering Low->1, Medium->2, High->3.