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COMPUTER SOFTWARE APPLICATION - CITS




           Disadvantages of ACID Properties in DBMS
           1  Performance:  The  ACID  properties  can  cause  a  performance  overhead  in  the  system,  as  they  require
              additional processing to ensure data consistency and integrity.
           2  Scalability: The ACID  properties  may  cause  scalability  issues  in  large  distributed  systems  where  multiple
              transactions occur concurrently.
           3  Complexity: Implementing the ACID properties can increase the complexity of the system and require significant
              expertise and resources.

              Overall, the advantages of ACID properties in DBMS outweigh the disadvantages. They provide a reliable and
              consistent approach to data
           4  management,  ensuring  data  integrity,  accuracy,  and  reliability.  However,  in  some  cases,  the  overhead  of
              implementing ACID  properties  can  cause  performance  and  scalability  issues.  Therefore,  it’s  important  to
              balance the benefits of ACID properties against the specific needs and requirements of the system



            Joining of tables


           Joining tables is a fundamental operation in relational databases that allows you to combine data from two or
           more tables based on a related column. This operation is crucial for querying and analyzing data stored in a
           database. There are several types of joins in SQL, the most common being INNER JOIN, LEFT JOIN (or LEFT
           OUTER JOIN), RIGHT JOIN (or RIGHT OUTER JOIN), and FULL JOIN (or FULL OUTER JOIN).
           1  INNER JOIN
              •  Returns only the rows that have matching values in both tables.
              •  Rows that do not have a match in the other table are excluded from the result set.




























           Syntax
           SELECT columns
           FROM table1
           INNER JOIN table2 ON table1.column = table2.colum

           2  LEFT JOIN (LEFT OUTER JOIN)
              •  Returns all rows from the left table and the matched rows from the right table.
              •  If there is no match in the right table, NULL values are included for the columns from the right table.




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                              CITS : IT&ITES - Computer software application - Lesson 18 - 36
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