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Format of the Species Database.

Details of the tables.

2. There are also a number of tables related to the main table that are used in queries. These are all linked to the main table in such a way as to ensure the integrity of the information they contain. This will be explained later. These tables are:-

Edible use details. Medicinal use details. Other use details.

3. The following tables are linked to the respective `....use details' tables listed above. This will be explained more fully later. 'Edible uses' 'Medicinal uses' 'Other uses'

4. Cultivars. A lot of work needs to be done on this table. Basically it will be a list of useful cultivars and it will be linked to the main table. At present (28/09/94) it only contains details of about 300 cultivars that we are growing and will not normally be issued with copies of the database.

5. Habitats. This table has been added to the Access version of databases we send out as of January 1996. It is not complete, but gives suggested habitats for plants in the garden. Your comments on this table will be greatly appreciated.

Types of fields used in the database.

A description of the field types used in all these database tables:-

Text

The entry is a mixture of letters and numbers and can range in size from 1 to 255 characters

Memo

As above but the size can go up to 32,000 characters. Great for entering longer details but not very good for pulling out specific information.

Yes/No

The best field for retrieving information from quickly, it only takes up 1 bit of memory, this is one eighth of the memory needed to store a single character such as a letter. It does have limitations though because it always says either yes or no and does not allow the possibility of a don't know answer by leaving the entry blank. Some of the yes/no fields have been changed to a text field of 1 byte to allow the possibility of entering Y for yes, N for no or leaving it blank where we have no information. This does take up to 8 times as much memory, with a consequent slowing down of information retrieval but it is often more informative.

Number

The field contains numbers only, other characters are not accepted in these fields.

Date

Shows the date in the format day/month /year viz:- 31/12/94.

Forms.

A number of forms are supplied with the Microsoft Access version of this database. These are:-

Species database 1. This form contains all the fields from the table `Species database'. It also contains three related forms, `Edible use subform', `Medicinal use subform' and `Other use subform'. This enables all the plant information to be read at one time as well as being the main form I use for adding and amending information in the database. This form is best viewed at a resolution of 800 x 600 or greater.

Species database 640. For those of you with lower resolution monitors, or notebooks, this form works well at 640 x 480 pixels.

Info sheet - species. This is a cut-down version of the `Species database 1' form. It contains most of the information we hold on each plant but omits most of the short fields we use in making queries. This form is issued as an information sheet and used by us as an easy way of reading about the plant.

Info sheet - cultivars. This is virtually the same as the previous form, but also includes information on individual cultivars.

Cultivars. This gives information specific to cultivars.

Books. Details the books that have been consulted in building up the database.

AddHabitats. Suggestions for habitats in the garden where plants can be grown.

Queries and Macros

There are also some queries and macros supplied with the Microsoft Access version of this database. These are used to perform various operations within the database, but do not need to be explained here. Unless you are conversant with using databases I would suggest that you just ignore these and leave them alone to get on with their work.

Plant information taken from the Plants For A Future - Species Database.
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