Using Caché Multi-Dimensional Storage - InterSystems ...

Table of Contents
1 Introduction ..................................................................................................................... 1
1.1 Features .................................................................................................................... 1
1.2 Examples .................................................................................................................. 3
1.3 Use in Applications .................................................................................................. 4
2 Global Structure .............................................................................................................. 5
2.1 Logical Structure of Globals .................................................................................... 5
2.1.1 Global Naming Conventions .......................................................................... 5
2.1.2 Subscript Naming Conventions and Limits .................................................... 6
2.1.3 Global Data ..................................................................................................... 7
2.1.4 Global Subscripts ........................................................................................... 8
2.1.5 Collation ......................................................................................................... 8
2.2 Physical Structure of Globals ................................................................................... 8
2.2.1 How Globals Are Stored ................................................................................. 9
2.3 Referencing Globals ............................................................................................... 10
2.3.1 Setting Global Mapping ............................................................................... 10
2.3.2 Extended Global References ........................................................................ 11
3 Using Multidimensional Storage (Globals) ................................................................. 15
3.1 Storing Data in Globals .......................................................................................... 15
3.1.1 Creating Globals ........................................................................................... 15
3.1.2 Storing Data in Global Nodes ...................................................................... 16
3.1.3 Storing Structured Data in Global Nodes ..................................................... 17
3.2 Deleting Global Nodes ........................................................................................... 18
3.3 Testing the Existence of a Global Node ................................................................. 19
3.4 Retrieving the Value of a Global Node .................................................................. 19
3.4.1 The $GET Function ...................................................................................... 20
3.4.2 The WRITE, ZWRITE, and ZZDUMP Commands ..................................... 20
3.5 Traversing Data within a Global ............................................................................ 20
3.5.1 The $ORDER (Next / Previous) Function .................................................... 20
3.5.2 Looping Over a Global ................................................................................. 22
3.5.3 The $QUERY Function ................................................................................ 23
3.6 Copying Data within Globals ................................................................................. 24
3.7 Maintaining Shared Counters within Globals ........................................................ 24
3.8 Temporary Globals ................................................................................................. 25
Using Caché Multi-Dimensional Storage
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