With ENUM you get same storage efficiency (or even better) than SMALLINT, but the ease of use of a VARCHAR data type. This is where ENUM makes sense: CREATE TABLE country_continent (Ĭontinent ENUM('Africa', 'America', 'Antarctica', 'Asia', 'Europe', 'Oceania') INSERT INTO country_continent VALUES ('Paris', 3) INSERT INTO country_continent VALUES ('New-York', 2) INSERT INTO country_continent VALUES ('Kenya', 1)
INSERT INTO continents VALUES (3, 'Europe') INSERT INTO continents VALUES (2, 'America') To quickly get started with Nessus, use the Basic Network Scan template. To see a full list of the types of templates available in Nessus, see Scan and Policy Templates. Some templates are only available when you purchase a fully licensed copy of Nessus Professional. INSERT INTO continents VALUES (1, 'Africa') The Nessus interface provides brief explanations of each template in the product. INSERT INTO country_continent VALUES ('Paris', 'Europe') įor better storage efficiency you'd better use SMALLINT (2 bytes) instead of VARCHAR (generally 1 byte + the Length of the string) for the continent field: CREATE TABLE continents ( INSERT INTO country_continent VALUES ('New-York', 'America') INSERT INTO country_continent VALUES ('Kenya', 'Africa') Using VARCHAR CREATE TABLE country_continent ( Let's take your example with a table listing the countries and their respective continents. 3.ENUM datatype can be seen as a "human-readable" numeric value, commonly used for convenience and data storage efficiency. This might turn out to be a significant issue when we need to deal with a high volume of data. However, renaming an enum value will still break the database data.Īdditionally, even though this data representation is far more readable compared to the option, it also consumes a lot more space than necessary. With we can safely add new enum values or change our enum's order. JPA will execute the following SQL statement: insertīinding parameter as. Now when persisting an Article entity: Article article = new Article()
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