Basic search is useful and will fulfill most of the users' search needs. However, there are still some limitations. One such limitation is that basic search allows you to perform searches based on inclusive logic but not exclusive logic. For example, if you need to search for issues in all but one project, with basic search, you will have to select every project except for the one to be excluded, since the basic search interface does not let you specify exclusions, and this is where advanced search comes in.
With advanced search, instead of using a field selection-based interface as in basic search, you will be using what is known as the JIRA Query Language (JQL). JQL is a custom query language developed by Atlassian. If you are familiar with the Structured Query Language (SQL), you will notice that it has a similar syntax; however, JQL is not the same as SQL.
One of the most notable differences between JQL and SQL is that JQL does not start with a select statement...