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CIS-145 FinalCIS-145 Final
• 100 points• Open book, open notes, open
computer• True-false, multiple choice, fill-in,
short answer
DatabasesDatabases
• Collection of related information– Scope is based on what information we
need to complete tasks
• Access uses seven objects to organize and manage data– Tables, queries, forms, reports,
macros, modules– All objects are in one file
TablesTables
• Fields are individual data elements/values - columns
• Records are the collection of data for one occurrence – rows
• Table should be about one thing or idea
• Primary key uniquely identifies each record
Table DesignTable Design
• Include all necessary data• Store data in smallest parts• Don’t include calculated fields
Field Data TypesField Data Types
Common Types• Number• Currency• Text• Yes/No• Date/Time
What kind of data will be stored in the field?
Numbers not used for calculations should usually be text.
PropertiesProperties
• Set specific characteristics and behaviors of objects (fields, controls, or other objects)
• Properties set for a field are inherited by controls that refer to that field– Drag field from field list in form design
view
Data ValidationData Validation
• Need to make sure we have good data - proper type and values
• Properties can help with validation:– Field Size: How much data to accept– Input Mask: How or what data is
entered– Format: How data is displayed– Validation Rules: What data is
acceptable– Required: value must be entered
Relational DatabasesRelational Databases
• Have more than one table where tables are related to each other– One to one– One to many– Many to many
• A combination of fields may be used for the table’s key
One to Many One to Many RelationshipsRelationships
• Each table contains data about a specific subject (customers, loans)
• Each table on the ‘one’ side has a primary key
• Primary key of the “one” table is used to create a foreign key in the “many” table
Many to Many Many to Many RelationshipsRelationships
• Two tables are related, but can have many records in each table in common– One student can attend many courses;
one course can be attended by many students
• Implement a many to many relationship by creating a pair of one to many relationships with a third (join) table
Foreign KeyForeign Key
• A foreign key points to a record in another table
• Foreign key “looks like” the related primary key– Same number of fields– Data types for each field must match– Field names don’t matter
Referential IntegrityReferential Integrity
• Makes sure that the records in related tables are consistent– Must have a customer in the customer
table for an order assigned to that customer
– Avoids “orphans”
• Can’t delete a record or change the primary key in the one table when associated records are in the many table, unless have cascade delete and cascade update enabled
Relationships WindowRelationships Window
• Where relationships between tables are created and defined
• Related fields must have the same data type– Autonumber is related to number field
with long integer field size
• The one table has a 1 next to it; the
many has a next to it
Select QueriesSelect Queries
• Select Queries represent a question and an answer
• Question is created in design view– Design view creates a Structured
Query Language (SQL) statement
• Answer is shown in datasheet view– Answer is a dynaset - dynamic subset
of a table
Query DesignQuery Design
• Specify data source - table or another query (FROM)
• Determine which rows to include (WHERE)
• Identify groups (GROUP BY)• Specify groups to include in result
(HAVING)• Identify fields to include in result
(SELECT) • Specify how to sort the answer (ORDER
BY)
And Or
CriteriaCriteria
WildcardsWildcards
• ‘*’ is for a group of characters (0, 1 or more characters)
• ‘?’ is for a single character (and there must be a character)
“S*ND” will return sand, sound, send, stand, spend
“S?ND” will return sand, send
Total QueriesTotal Queries
• Select query with results summarized by one or more fields– Find value(s) that records share and
summarize information
• Similar to Groups in a Report
Multi-table QueriesMulti-table Queries
• Can use multiple tables in a query• If tables are not already related,
can connect tables in the query itself– Drag the connecting field from the one
table to the many table
• “Joins” describe how rows in one table match rows in the other table(s)
JoinsJoins
• When using multiple tables, need to connect through a join
• Inner-join is most common and requires matching values in both tables
• Outer-join includes all rows from one table and any matching records from second table that exist
• Cartesian Join matches all rows from one table with all rows from 2nd table
Autolookup QueriesAutolookup Queries
• Use queries to automatically look up data from related tables
• Must contain the foreign key from the many table– Value entered in foreign key is
matched to value in related primary key to “look up” data
• Can add, change or delete data in the source tables– Many side will determine where a new
row is added or existing row deleted
Parameter QueriesParameter Queries
• Parameter queries allow entry of criteria when query is run– A “place holder” allows the criteria to
be saved without a specific value– Behaves like an argument in other
programming languages
• Allows query to be used with different values without having to go into design view
Action QueriesAction Queries
• Action queries are about change• Can change data
– Update: change an existing value– Append: add rows to a table– Delete: remove rows from a table
• Can change database– Make-table: create a new database
object
FormsForms
• Basic use is to enter and display information from a table– Forms can also help to change data
stored in table by being bound (record source is a table or query)
• Forms can help others use an application•Typically an unbound form (no
record source)• Forms use controls: bound, unbound,
calculated
Forms - 2Forms - 2
• Forms have sections: header, footer, and detail– Detail section is used to display data
from one row in a table or query
• Tab order controls how the cursor moves through controls on a form
Forms & SubformsForms & Subforms
• Main form is based on the primary (“one”) table
• Subform is based on the many table• Subform shows records associated
with the current record in the primary table
• Each form has its own status bar, record selector, and navigation buttons
SubformsSubforms
• Main form and subform are linked through specific fields; fields don’t have to be shown, but must be in data source (record source)
• A main form can have several subforms• Subforms can be displayed as a data
sheet, single form or continuous forms– Display is set through the form’s
default view in the properties window
List ControlsList Controls
• A list or combo box can be bound to a field in one table, and display data from fields in a second table– Good choice for selecting a value for a
foreign key, if the primary and foreign keys are single fields
• Rowsource property specifies the list of choices, bound column specifies the value to save
• Can show/not show different columns in the list
ReportsReports
• Displays information from a table or query
• Cannot change data– A report shows the data at the time of
printing or print preview– Each time a report is displayed or
printed, it recalculates and re-reads the data from tables, so one report can show different values
Reports - 2Reports - 2
• Reports have sections: report, page, and group headers and footers; and detail
• Controls are used to display data, information, calculations– The most common controls are text
boxes, labels, and lines
Sorting & GroupingSorting & Grouping
• Groups help to organize data into information for records that have something in common– Can summarize information for
subgroups (for example, showing subtotals by location)
• Sorting controls the order that information is shown
SubreportsSubreports
• Allow main report to include all records, regardless of whether there are related records– Subreports are similar in function to
subforms, finding related rows for the current row in main report
• Can include several subreports, if a query would create incomplete or duplicating results
Getting & Using Data in Getting & Using Data in Forms and ReportsForms and Reports
• Forms and reports have a recordsource property– Can get data from a table or query
• Bound controls use the controlsource property to connect to a field– Field for controlsource must be in form
recordsource– Controlsource is also used for
calculations