Top Most How to create and call stored procedure in MySQL with IN and OUT parameters

It's hard to remember exact syntax of, how to create stored procedure in MySQL, until you are creating and working on stored procedure frequently, simply because syntax is not a one liner. You need to remember exact syntax, if you are using MySQL database from command line. What help in this case is, quick examples. In last couple of MySQL tutorial we have seen How to find second highest salary and How to join 3 tables in one query; In this MySQL tutorial we will see couple of examples of creating stored procedure and calling stored procedure using IN and OUT parameters. All these MySQL examples are simple and help you to understand syntax of creating stored procedure with parameters in MySQL. These examples are tested in MySQL 5.5 database. We will also use following employee table to create and test these stored procedures :
 

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Top Most Difference between LEFT and RIGHT OUTER Joins in SQL - MySQL Join example

There are two kinds of OUTER joins in SQL, LEFT OUTER join and RIGHT OUTER join. Main difference between RIGHT OUTER join and LEFT OUTER join, as there name suggest, is inclusion of non matched rows. Sine INNER join only include matching rows, where value of joining column is same, in final result set, but OUTER join extends that functionality and also include unmatched rows in final result. LEFT outer join includes unmatched rows from table written on left of join predicate. On the other hand RIGHT OUTER join, along with all matching rows, includes unmatched rows from right side of table. In short result of LEFT outer join is INNER JOIN + unmatched rows from LEFT table and RIGHT OUTER join is INNER JOIN + unmatched rows from right hand side table. Similar to difference between INNER join and OUTER join, difference between LEFT and RIGHT OUTER JOIN can be better understand by a simple example, which we will see in next section. By the way joins are very popular in SQL interviews, and along with classic questions like finding second highest salary of employee,Inner join vs outer join or left outer join vs right outer join is commonly asked.

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Top Most Migrating SQL Query from Oracle to SQL Server 2008 or Sybase

Oracle and Microsoft SQL Server are very different than each other and if you are migrating SQL queries or database, tables from Oracle 11g database to Microsoft 2008 SQL server than you are bound to face some issues. Main reason of these porting issues are features, which are supported and exists in Oracle database, but not available in Microsoft SQL Server 2008 like SEQUENCE, Order by clause in sub queries and derived tables, derived table without name etc. I am sure there are few more and it will surface based upon different database objects you are using in your tables and queries. On other hand SQL Engine for SQL Server and Sybase are very much similar, at least syntactically, and if you are migrating queries from SQL Server to Sybase you can do that without much hassle, of course there will be slight changes but not as much like Oracle. So if you are migrating from Oracle to Sybase or SQL Server its most likely same job and you should first start with either SQL Server or Sybase ASE and than later migrate them from each other. In this Oracle and SQL Server tutorial we will see couple of examples, where Oracle and SQL Server are different and how to change those SQL queries so that it can run on Microsoft SQL Server. By the way I have also written couple of post on queries like 10 ways to use SQL SELECT queriesand Don’t delete, truncate it. If you like reading more on SQL queries than those are for you.

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