In SAP, tables could be categorized as Application tables and Customizing tables. Apart from these categories there are other ones which are reserved for internal usage. Application tables are mostly used for holding master and transactional data whereas Customizing tables holds customer specific data which customize your SAP system according to your needs.
As you all know ABAP uses Open SQL to carry out database operations. SQL operations have CRUD(Create, Read,Update, Delete) functionalities. Before carrying out these four type operations first we need to filter our data according to a WHERE condition. This filtering can also be done dynamically by forming up the where condition with string operations. For example an SQL statement where querying LH carrid airlines can also be written dynamically as the following.