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=== Linear organization ===
A '''linear data set''' (LDS) is a type of [[data set (IBM mainframe)|data set]] organization used by VSAM.<ref name="demystified"/>{{rp|5}} The LDS has a control interval size of 4096 bytes to 32768 bytes<ref>{{cite manual|title = z/OS 2.5 DFSMS Using Data Sets|id = SC23-6855-50| section = Linear Data sets| section-url = https://www-01.ibm.com/servers/resourcelink/svc00100.nsf/pages/zOSV2R5sc236855/$file/idad400_v2r5.pdf#page=126|page = 91|date = September 30, 2021|url = https://www-01.ibm.com/servers/resourcelink/svc00100.nsf/pages/zOSV2R5sc236855/$file/idad400_v2r5.pdf|publisher = IBM}}</ref> in increments of 4096.<ref name="demystified"/>{{rp|31}} A LDS does not have embedded control information, because it does not contain control information, the LDS cannot be accessed as if it contained individual records.<ref>{{Cite web|title=IBM Knowledge Center|url=https://www.ibm.com/support/knowledgecenter/en/SSLTBW_2.1.0/com.ibm.zos.v2r1.idad400/d4261.htm|access-date=2021-02-07|website=www.ibm.com| date=27 March 2014 |language=en-US}}</ref>
Addressing within an LDS is by Relative Byte Address (RBA), which allows it to be used by systems such as [[IBM Db2]] or the Operating system.{{huh|date=April 2021}} The benefit of this is that systems such as the OS can access multiple disk spindles and view it as a single storage implementation. The limitations of this, though, is that this does not make this particularly useful to higher level abstraction levels.{{or|date=April 2021}} Data In Virtual{{sfn|ASMGUIDE|loc=Chapter 14. Data-in-virtual|pp=[https://www.ibm.com/servers/resourcelink/svc00100.nsf/pages/zOSV2R5sa231368/$file/ieaa600_v2r5.pdf#page=253 225-248]}} (DIV) and Window services{{sfn|ASMGUIDE|loc=Chapter 17. Window Services|pp=[https://www.ibm.com/servers/resourcelink/svc00100.nsf/pages/zOSV2R5sa231368/$file/ieaa600_v2r5.pdf#page=321 293-310]}} provide an alternative method to direct use of VSAM to access an LDS with a CI size of 4096.
== Data access techniques ==
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* [http://www.redbooks.ibm.com/abstracts/sg246105.html?Open VSAM Demystified]
* [https://www-304.ibm.com/servers/resourcelink/svc00100.nsf/pages/zOSV2R3SC236877/$file/idat100_v2r3.pdf DFSMStvs Overview and Planning Guide]
==Further reading==
;ASMGUIDE
:{{cite manual
| title = z/OS 2.5 MVS Programming: Assembler Services Guide
| id = SA23-1368-50
| date = September 30, 2021
| url = https://www.ibm.com/servers/resourcelink/svc00100.nsf/pages/zOSV2R5sa231368/$file/ieaa600_v2r5.pdf
| ref = {{sfnref|ASMGUIDE}}
| publisher = IBM
}}
{{Mainframe I/O access methods}}
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