Search results: learn sql

the distinct keyword in sql is used in conjunction with the select statement to remove all duplicate records and retrieve only records.

to sort data in sql, we use the order by clause.

in sql, the join clause is used to combine records from two or more tables in a database using common values ​​from each table.

inner join in sql is the most important and often used join type.

the left join in sql is the type of join that returns all records from the left table and matching records from the right table.

right join in sql is a type of join that returns all records from the right side table and matching records from the left side table.

full join in sql returns all records in the left table and the table must combine and fill in that null values ​​for values ​​do not match.

cartesian join in sql returns the cartesian product of record sets from two or more combined tables.

null in sql is the term used to represent a missing value.

sql alias is used to create a temporary name (called an alias) for a column or table.

sql index (index) is a special lookup table that database search engines can use to quickly increase the time and performance of data retrieval.

the alter table statement in sql is used to add, delete, and modify columns in an existing table.

the and and or operators are used to combine multiple conditions to narrow the data in sql statements. these two operators are called conjugate operators in sql. and and or allow

sql is a familiar term if you pay attention to the computer field. so what do you know about sql?

continue series what do you know about sql? , part 2 continues with questions that revolve around basic knowledge in databases.

the test set comes with sql lessons that give you lots of useful knowledge.

let's try our knowledge with multiple choice questions about sql database management system.

multiple-choice questions on sql help you familiarize and review useful knowledge for work and learning sql language.

in order to serve your work and your study, along with sql lessons, quantrimang offers a variety of useful questions.

part 7 of the sql quiz goes into the sql practice exercises that follow the previous period.