If we need to group rows with the same values into summary rows, we use GROUP BY. Cate RichterI give people clear, functional, and proven instructions. I gently guide them so that they can fulfill their IT dreams. Read my story here >> caterichter.com
The DELETE statement allows you to delete data from a table. The table structure remains in the database. This command is often confused with DROP as it deletes data and the table structure from the database. Cate RichterI give people clear, functional, and proven instructions. I gently guide them so that they can fulfill their …
Selft join is a particular type of join. The difference is that the table pairs on itself. It is very often used, for example, to find an employee and his superior. Cate RichterI give people clear, functional, and proven instructions. I gently guide them so that they can fulfill their IT dreams. Read my story …
The UPDATE statement allows you to change the data in a table. Cate RichterI give people clear, functional, and proven instructions. I gently guide them so that they can fulfill their IT dreams. Read my story here >> caterichter.com
The TRUNCATE statement deletes a table from the database. This means that there will be no data from the table in the database, nor will there be a defined table structure. Cate RichterI give people clear, functional, and proven instructions. I gently guide them so that they can fulfill their IT dreams. Read my story …
Returns records when we have the corresponding foreign key in the table after FULL JOIN. We have complete data from the right and left tables. Cate RichterI give people clear, functional, and proven instructions. I gently guide them so that they can fulfill their IT dreams. Read my story here >> caterichter.com
The DROP statement deletes a table from the database. Neither data from the table in the database nor a defined table structure will appear. Cate RichterI give people clear, functional, and proven instructions. I gently guide them so that they can fulfill their IT dreams. Read my story here >> caterichter.com
With ALTER we can modify an existing table. We can add, delete, edit fields in the table. Cate RichterI give people clear, functional, and proven instructions. I gently guide them so that they can fulfill their IT dreams. Read my story here >> caterichter.com
Returns records when we have the corresponding foreign key in the table after RIGHT JOIN. This is true even if they do not match the following table. On the right table we have complete and additional information from the left table, only if they exist. Cate RichterI give people clear, functional, and proven instructions. I …
The database has defined data types that express the nature of the data. We can store text (for example, VARCHAR, VARCHAR2), or numbers (for example, INTEGER, NUMBER), date (for example, DATE, TIMESTAMP), etc. Cate RichterI give people clear, functional, and proven instructions. I gently guide them so that they can fulfill their IT dreams. Read …