SQL Data Types Each column in a database has a data type. A data type is a set of values. There are different categories for data types: Approximate numeric: It stores approximations of the numbers based on IEEE 754 standard. float(N): Values in the range from -1.79E+308 to 1.79E+308. real: Values in the
SQL JOIN Self Join: Self join is used to join table with itself. Syntax: select column_name(s) from table1 A1,table2 A2 where condition; Here, A1 and A2 are different alias name for the same table. Database Table: Customers Cust_id Name Age City 1 Prince 22 Anand 2 Komal 44 Pune 3 Khusi 30 Delhi 4 Anil 45 Mumbai 5 Abhi 27 Ahmedabad 6 Juhi 35 Baroda Here, Cust_id is primary key. Example-1: select x.Name as Name1, x.Age as Age1, x.City as City1, y.Name
SQL JOIN Cross Join: Cross join combine each row from the first table with all rows of the second table. In other words, it performs a multiplication between tables. Cross join is also known as Cartesian Join. Syntax: select column_name(s) from table1 cross join table2 We can perform cross join without join clause.