Some people have used Interbase for a while, complaining that the data type provided by InterBase is too small. Indeed, Interbase does provide a number of data types than other relational databases, but in fact, as long as you think with your heart, you will find that Interbase's domain object can help us extend a lot on the basis of basic data types. type of data. In fact, after this expansion, you will find the data type of Interbase basically and Sybase11.9, the data type provided by the MS SQL Server2000. 1, logical data type Boolean (value range 0 or 1) There are two ways to implement the Boolean logic type. One of the methods: Use integer 0 and 1 representative logic truth and false. Create Domain Boolean As Smallint Default 0 Check (Value In (0,1)); Method 2: Use characters '0' and '1' representing logic truth and false. Create Domain Boolean As Char Default '0' Check (Value In ('0', '1')); 2, currency data type MONEY, SMALLMONEY Since the interbase6.0 Dialect 3 has implemented large precision data, you can use Numeric Type constructs a currency type. Money Type: Create Domain Money As Numeric (18, 4); SmallMoney Type: CREATE DOMAIN SMALLMOMONEY As Numeric (9, 4); You can change the length and decimal number of points according to the actual situation to make it in line with your requirements. 3, other integer type Tinyint, bigint tinyint type (0 ~ 255): Create Domain Tinyint AS Integer Check (Value Between 0 and 255); Bigint Type (63 times of -2): CREATE Domain Bigint As Numeric (18, 0); 4, Image Type Image Conforms through the BLOB type subtype. CREATE DOMAIN Image As Blob Sub_Type 0 5, text type text is constructed by a bioc type subtype. CREATE DOMAIN TEXT AS BLOB SUB_TYPE 1 6, the user-defined data type use domain, you can create a variety of custom data types like other relational databases.
