Memo Field Size

[AdmSteck]

How much memory is needed to store memo fields? Would it be more efficient
to create a large text field?

 

[Rick Brandt]

How much memory is needed to store memo fields? Would it be more efficient
to create a large text field?

In a memo field all that is stored in the table is a pointer to the actual data
stored elsewhere on disk (still within your file). The amount of space consumed
should be the amount of your data plus the small amount for the pointer. If you
need more than 255 characters then a Memo field is the appropriate choice.

The more "real" issue with Memo fields in Jet tables is that they can be prone
to corruption so you should be prudent with them. I usually ask my users if
they _really_ need more than 255 characters before I use them.

 

[John Vinson]

How much memory is needed to store memo fields? Would it be more efficient
to create a large text field?

A Text field is limited to 255 bytes, so there's no such thing as a
"large text field". A Memo stores as many characters as are entered
into the field, plus a 16-byte overhead no matter the size of the memo
field. Thus if you have 40 bytes in the memo field, it will take up 56
bytes on disk; if you have 40,000 bytes, it will take up 40,016 bytes.

If you don't need more than 255 bytes, use Text; text fields are more
efficient, they can be indexed, and they're less subject to corruption
than Memos.

John W. Vinson[MVP]
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[AdmSteck]

Ok, do text fields store the same way, or do they always allocate the field
size whether it is used or not?

 

[Rick Brandt]

Ok, do text fields store the same way, or do they always allocate the field
size whether it is used or not?

Access Text fields are variable length (unless you go out of your way to make
them fixed width) They only consume as much space as the characters stored in
them (plus a little more). So a 255 character field with only 10 characters
entered in it does use less disk storage than if you had entered 50 characters.