Wildcards are special characters that can stand in for unknown characters in a text value and are handy for locating multiple items with similar, but not identical data. Wildcards can also help with getting databased on a specified pattern match. Access supports two sets of wildcard characters because it supports two standards for Structured Query… Read More »
In this chapter, let us understand Many-to-Many Relationship. To represent a many-tomany relationship, you must create a third table, often called a junction table, that breaks down the many-to-many relationship into two one-to-many relationships. To do so, we also need to add a junction table. Let us first add another table tblAuthers. Let us now create… Read More »
The vast majority of your relationships will more than likely be this one to many relationships where one record from a table has the potential to be related to many records in another table. The process to create one-to-many relationship is exactly the same as for creating a one-to-one relationship. Let us first clear the… Read More »
Let us now understand One-to-One Relationship in MS Access. This relationship is used to relate one record from one table to one and only one record in another table. Let us now go to the Database Tools tab. Click on the Relationships option. Select tblEmployees and tblHRData and then click on the Add button to add them to our view and then close… Read More »
In this chapter, we will understand the need to create relationships between related tables. One of the goals of good database design is to remove data redundancy. To achieve that goal, you divide your data into many subject-based tables so that each fact is represented only once. To do this, all the common fields which… Read More »
In this chapter, we will understand the basics of relating data. Before talking about and creating relationships between different data, let us review why we need it. It all goes back to normalization. Normalization Database normalization, or simply normalization, is the process of organizing columns (attributes) and tables (relations) of a relational database to minimize… Read More »
Queries come in with many advantages. You can save and run the same query again and again, and a lot of times you want to add alternate criteria. You can add alternate criteria in the following two ways − You can use the OR operator to combine two sets of criteria. You can also use… Read More »
The best part about queries is that you can save and run the same query again and again, but when you run the same query again and again by only changing the criteria then you might consider the query to accept parameters. If you frequently want to run variations of a particular query, consider using… Read More »
Create an Update Query You can use an Update Query to change the data in your tables, and you can use an update query to enter criteria to specify which rows should be updated. An update query provides you an opportunity to review the updated data before you perform the update. Let us go to… Read More »
In MS Access and other DBMS systems, queries can do a lot more than just displaying data, but they can actually perform various actions on the data in your database. Action queries are queries that can add, change, or delete multiple records at one time. The added benefit is that you can preview the query… Read More »