Used to indicate the internal type of the data type. The possible types are:
- Alphanumeric: character string with a maximum length of 255 characters, where the length can be given in the corresponding section. If the length is not given, it will be given by the length of the field at the time of using the type.
- Local menu: integer between 1 and 255.
- Short integer: integers between -32768 and 32767.
- Long integer: Integers between -2^31 et +2^31-1.
- Decimal: This is a numeric field with up to 32 significant figures, whose length is given in the form N.M (N being the number of figures before the decimal point and M being the number of figures after). This length can be given directly at the level of the type or in the length field defined at the level of the field that will use this type. According to the database, this type of field can be stored in the floating or fixed form in the database. In the first case, which corresponds to Oracle: in this case, what counts, when a N.M format is defined is in reality the total precision of the storage – N+M – . The second case corresponds to SQLServer: the number of positions before and after the decimal point must be clearly defined. The format field (which can be variable) will then define more precisely the distribution of the figures between the whole number section and the decimal section.
- Date: this is the date comprised between the 1st January 1600 and 31st December 9999 (remembering that a null date symbolised by [0/0/0] exists).
- Blob: it is used to store and manage the images.
- Clob: it is used to store in the database variable length texts with the format "rtf" or "txt" and to manage them.
For the blobs as with the clobs, it is necessary to enter the length that will be maximum storage length. The coding is as follows:
Length | Memory size | Maximum characters |
0 | 1020 | 510 |
1 | 2044 | 1022 |
2 | 4092 | 2046 |
3 | 8188 | 4094 |
n | 1024*(2^n) - 4 | 512*(2^n) - 2 |
Floatingand Double are the types that will not be recommended for use (formats linked to the machine).