Advantage Database Server

More Efficient Memo Block Size

Advantage Concepts

More Efficient Memo Block Size

Advantage Concepts

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More Efficient Memo Block Size

Advantage Concepts

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Advantage proprietary ADM memo files have a default storage block size of 8 bytes. If anywhere from 1 to 8 bytes of memo data is stored, a single 8-byte block in the memo file will contain the data. If 9 to 16 bytes of data is stored, two consecutive 8-byte blocks in the memo file will contain the data. Due to its smaller storage block size, ADM memo files are much more efficient at memo data storage than are Xbase memo files.

For example, if the word "Kayak" is stored in an ADM memo file, it will fit in a single 8-byte memo block. On the other hand, with an Xbase FPT memo file, it would take 64 bytes and an Xbase DBT memo file 512 bytes to store this 5 character word. If an additional 60 characters are added to the memo field, the ADM memo file finds and uses 9 contiguous 8-byte memo blocks in the "free list" to store the new memo data. With an Xbase FPT memo file, it would take 128 bytes and an Xbase DBT memo file 512 bytes to store this 65 character value.

Due to the Advantage proprietary memo file format’s small block size, ADM memo files store memo data very efficiently. If reducing memo file size bloat is an issue, you may want to use the Advantage Proprietary Format.