Caché Upgrade Checklists - InterSystems Documentation

Caché 2008.2 Upgrade ChecklistWhen one of the name parts is truncated, the truncated portion is encrypted to help create a unique name. In previous versions,this encryption produced a three-character string. Beginning with this version of Caché, the algorithm produces a fourcharacterstring.CAUTION:If an application has external class definitions that do not include storage definitions, it is possible thatrecompilation of the class will produce a storage structure incompatible with existing data.7.2.1.6 $SYSTEM.Task To Be RemovedCaché version 5.2 moved the task manager classes from %SYSTEM.Task to %SYS.Task. The documentation for the classwere changed to indicate that the %SYSTEM.Task class was deprecated. Users were advised to change their applicationsto use %SYS.Task.Note:InterSystems intends to remove the %SYSTEM.Task and the corresponding $SYSTEM.Task classes in the nextversion of the product.7.2.2 Character Set Changes7.2.2.1 Support For Unicode-16 And JIS2004 AddedCaché introduced support for Unicode in version 3.0. In this first implementation, only characters in the Basic MultilingualPlane (BMP), that is, those in the range U+0000 to U+FFFF, were supported. Version 2007.1 introduced support forGB18030 in one- and two-byte values.This version extends that support to codepoints that result in Unicode surrogate pairs. These are pairs of 16-bit charactersthat, taken as a unit, represent Unicode characters outside the BMP. A surrogate pair consists of a high-order and a lowordercode. The high word ranges from U+D800 to U+DBFF and the low word from U+DC00 to U+DFFF. When interpretedas a UTF-16 character, these pairs map from U+10000 to U+10FFFF and cover one million code points. Unicode stringsthat contain surrogate pairs are said to be encoded in UTF-16.Existing ObjectScript string functions such as $Extract, $Find, and so on are not aware of surrogate pairs and thus canprovide inconsistent results when supplied with strings that may contain such pairs. This version of Caché introduces specializedversions of the regular string functions that correctly handle surrogate pairs. These functions are:• $WAscii• $WChar• $WExtract• $WFind• $WIswide• $WLength• $WReverseThese new functions must scan the string in order to determine the boundaries between the characters because some maybe represented by a single 16-bit value and others by surrogate pairs. For example, the 4 word sequence 0x41, 0xD800,0xDC00, 0x42 is a 3-character string if surrogate pairs are taken into account because the two middle words correspond toa single character, U+10000.172 Caché Upgrade Checklists