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Displaying posts with tag: sql sqlite mysql c php types untyped manifestation (reset)
Manifestation type

You may or may not have heard of it, SQLite has them, but what is a manifestation type (I'll call them mtypes from now on)?

You can think of an mtype as a untyped variable with a twist. That is you can assign anything you want to it without having to first declare its type OR size. But first lets look at a typed variable example using the C programming language. In C if you want to store a string you will need to declare a fixed char array or create a char pointer to some malloc'd memory cast as char:

// fixed length array
char str[28];

or

// malloc'd fixed length array
char *str;
str = (char)malloc(sizeof(char)*28);

You need to know ahead of time how much space you will need to store a string. If your string was longer than 28 characters you would lose everything after character 28, safely off course by being sure not to write more than 28 bytes ;) …

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