Washington State University



Featherman’s Glossary – Online VersionAs part of MIS325 you are given a database (or you are asked to create your own). Here is a glossary of the terms. In general databases store data that is stored in two-dimensional tables which have rows and columns. It would be very normal for example to have one database that has 10 tables in it. Each table would be used to store similar information for example having a Customers table and a Vendors table.Each of the tables has rows and columns. You specify the columns first, delineating the Active Data Objects (ADO) are a set of data connectivity objects created by Microsoft developers that fit into the .NET development environment. These ADO objects are tuned for speed of data retrieval and data manipulation (for example there are objects designed to work specifically with the SQL Server database). The list below represent some of the common ADO classes for the .NET development platform, thus called the objects.ArrayAn array is a grid, tabular shaped stack of variables. Arrays are useful and efficient for programs that need to store a lot of similar data in memory of the webpage. An example would be to store similar data for store 1, store 2, store 3 etc. of a chain store. An array can have one column (a vertical stack of the same datatype that looks like a ladder), or many columns such as 5 columns of data about an entity (store #, Store revenue, store # transactions, etc.) that looks like a grid.Arrays are great to receive and store data downloaded from a database table (used in the second half of the course) to facilitate data entry (ie populate all the list controls for a webpage) and to store temporary values in-memory for further processing and later storage.In data tables are the arrays that are utilized. These are ‘strongly typed’ arrays as columns can heave different datatypes (string, decimal, date, etc.)DataTableMicrosofts Array is implemented with the datatablr objerct. A datatable is an object that holds data in the memory of a webpage. We use datatables in two ways, the first of which is to store rows of transaction data (ie a sale) for later upload to the database. The transaction data rows are typically not updated, and rather are used as the dataset for later analytics.We also use datatables to store summary data for groups. For example for each girlscout troop we keep track of different measures related to cookie sales. This type of array is used to store updates and running totals, so the data changes to remain accurate.A datatable is a container used to hold data either generated in the web page or retrieved from the database. A database table refers to a table in a database. A datatable refers to an array stored in the memory of the webpage.A datatable is a strongly typed array, a programming object which serves as a two-dimensional tabular storage unit similar to an Excel spreadsheet. Datatables have columns which define the schema (column names, default values, whether NULLS are allowed, datatypes such as integers, and constraints such as primary and foreign keys). Datatables have rows which hold the data and an items collection which define the columns. You can use datatables as part of a dataset or by themselves without a dataset.DataGridView orgridviewThis is a grid looking control you place on a web form. It resembles a table of data (a spreadsheet) so use this control when you want to see many rows and many columns of data. You must set its datasource property, telling it to display a datatable.Data TypesThe different types of data that a column in a database table can hold. When you create a table in a SQL Server database, you need to choose the data type for each column. Similarly if you create a datatable in a webpage you need to assign some columns that match the data types of the data that will be stored. If you need to hold dates, then you specify the usage of a datetime column, if you need whole numbers then choose integer, numeric, etc.ItemsEach row in a datatable (a container that holds data in your webpage) has an items collection which are the columns. For example if you have a datatable with a column called “FirstName” then the first row of the datatable can be referred to as datatable.rows(0).items(“Firstname”).When you retrieve one row of data from the database for updating, the code above is the code that you could use to pull the data out of each column for the one row of data that is retrieved; for example textbox1.text = datatable.rows(0).items(“Firstname”).RowsThe data in a table is stored in its rows (aka records) collection (list of rows). The rows know what columns it has (its schema). Rows is used in both datatables and SQL Server database tables.SchemaSchemaThe structure of a table or database is referred to as its schema. The schema of a table refers to the column names, their data types (ex: integer, datetime, character, etc) and the primary and foreign keys (the relationships/constraints between the tables).?The schema of a database is a general term that refers to the tables of a database and how they connect to each other (what foreign key constraints are implemented, what look-up fields are specified). ................
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