XML Schema minOccurs maxOccurs default values

Question

I m wondering how the XML Schema specification handles these cases    lt xsd element minOccurs  1  name  asdf   gt    No maxOccurs given -  Is this the cardinality  1  1     lt xsd element minOccurs  5  maxOccurs  2  name  asdf   gt    I suppose this is simply invalid    lt xsd element maxOccurs  2  name  asdf   gt    Is this the cardinality  0  2  or  1  2    Is there an  official  definition on how the XML Schema spec handles these cases

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example   XML   lt  xml version  1 0  encoding  UTF-8   gt    lt  xml-stylesheet type  text xsl  href  country xsl   gt   lt country xmlns xsi  http   www w3 org 2001 XMLSchema-instance  xsi noNamespaceSchemaLocation  country xsd  gt       lt countryName gt Australia lt  countryName gt       lt capital gt Canberra lt  capital gt       lt nationalLanguage gt English lt  nationalLanguage gt       lt population gt 21000000 lt  population gt       lt currency gt Australian Dollar lt  currency gt       lt nationalIdentities gt           lt nationalAnthem gt Advance Australia Fair lt  nationalAnthem gt           lt nationalDay gt Australia Day  26 January  lt  nationalDay gt           lt nationalColour gt Green and Gold lt  nationalColour gt           lt nationalGemstone gt Opal lt  nationalGemstone gt           lt nationalFlower gt Wattle  Acacia pycnantha  lt  nationalFlower gt       lt  nationalIdentities gt       lt publicHolidays gt           lt newYearDay gt 1 January lt  newYearDay gt           lt australiaDay gt 26 January lt  australiaDay gt           lt anzacDay gt 25 April lt  anzacDay gt           lt christmasDay gt 25 December lt  christmasDay gt           lt boxingDay gt 26 December lt  boxingDay gt           lt laborDay gt Variable Date lt  laborDay gt           lt easter gt Variable Date lt  easter gt           lt queenBirthDay gt 21 April  Variable Date  lt  queenBirthDay gt       lt  publicHolidays gt       lt states gt           lt stateName gt  lt Name gt NSW -  New South Wales lt  Name gt  lt  stateName gt           lt stateName gt  lt Name gt VIC -  Victoria lt  Name gt  lt  stateName gt           lt stateName gt  lt Name gt QLD -  Queensland lt  Name gt  lt  stateName gt           lt stateName gt  lt Name gt SA -  South Australia lt  Name gt  lt  stateName gt           lt stateName gt  lt Name gt WA -  Western Australia lt  Name gt  lt  stateName gt           lt stateName gt  lt Name gt TAS -  Tasmania lt  Name gt  lt  stateName gt       lt  states gt       lt territories gt           lt territoryName gt ACT -  Australian Capital Territory lt  territoryName gt           lt territoryName gt NT -  Northern Territory lt  territoryName gt       lt  territories gt   lt  country gt    XSD    lt  xml version  1 0  encoding  UTF-8   gt    lt xs schema xmlns xs  http   www w3 org 2001 XMLSchema  gt       lt xs element name  country  gt           lt xs complexType gt               lt xs sequence gt                   lt xs element name  countryName  type  xs string   gt                   lt xs element name  capital  type  xs string   gt                   lt xs element name  nationalLanguage  type  xs string   gt                   lt xs element name  population  type  xs double   gt                   lt xs element name  currency  type  xs string   gt                   lt xs element name  nationalIdentities  gt                   lt xs complexType gt                       lt xs sequence gt                           lt xs element name  nationalAnthem  type  xs string   gt                           lt xs element name  nationalDay  type  xs string   gt                           lt xs element name  nationalColour  type  xs string   gt                           lt xs element name  nationalGemstone  type  xs string   gt                           lt xs element name  nationalFlower  type  xs string   gt                       lt  xs sequence gt                   lt  xs complexType gt                   lt  xs element gt                   lt xs element name  publicHolidays  gt                       lt xs complexType gt                           lt xs sequence gt                               lt xs element name  newYearDay  maxOccurs  1  type  xs string   gt                               lt xs element name  australiaDay  maxOccurs  1  type  xs string   gt                               lt xs element name  anzacDay  maxOccurs  1  type  xs string   gt                               lt xs element name  christmasDay  maxOccurs  1  type  xs string   gt                               lt xs element name  boxingDay  maxOccurs  1  type  xs string   gt                               lt xs element name  laborDay  maxOccurs  1  type  xs string   gt                               lt xs element name  easter  maxOccurs  1  type  xs string   gt                               lt xs element name  queenBirthDay  maxOccurs  1  type  xs string   gt                           lt  xs sequence gt                       lt  xs complexType gt                   lt  xs element gt                   lt xs element name  states  gt                       lt xs complexType gt                           lt xs sequence gt                               lt xs element name  stateName  minOccurs  1  maxOccurs  unbounded  gt                                   lt xs complexType gt                                       lt xs sequence gt                                           lt xs element name  Name  type  xs string   gt                                       lt  xs sequence gt                                   lt  xs complexType gt                               lt  xs element gt                           lt  xs sequence gt                       lt  xs complexType gt                   lt  xs element gt                   lt xs element name  territories  gt                       lt xs complexType gt                           lt xs sequence gt                               lt xs element name  territoryName  maxOccurs  unbounded   gt                           lt  xs sequence gt                       lt  xs complexType gt                   lt  xs element gt               lt  xs sequence gt           lt  xs complexType gt       lt  xs element gt   lt  xs schema gt    XSL    lt  xml version  1 0   gt    lt xsl stylesheet xmlns xsl  http   www w3 org 1999 XSL Transform  version  1 0  gt       lt xsl output method  html  indent  yes  version  4 0   gt       lt xsl template match     gt           lt html gt               lt body gt                             lt xsl for-each select  country  gt                                lt xsl value-of select  countryName   gt  lt br  gt                       lt xsl value-of select  capital   gt  lt br  gt                       lt xsl value-of select  nationalLanguage   gt  lt br  gt                       lt xsl value-of select  population   gt  lt br  gt                       lt xsl value-of select  currency   gt  lt br  gt                                     lt xsl for-each select  nationalIdentities  gt                           lt xsl value-of select  nationalAnthem   gt  lt br  gt                           lt xsl value-of select  nationalDay   gt  lt br  gt                           lt xsl value-of select  nationalColour   gt  lt br  gt                           lt xsl value-of select  nationalGemstone   gt  lt br  gt                           lt xsl value-of select  nationalFlower   gt  lt br  gt                       lt  xsl for-each gt                       lt xsl for-each select  publicHolidays  gt                           lt xsl value-of select  newYearDay   gt  lt br  gt                           lt xsl value-of select  australiaDay   gt  lt br  gt                           lt xsl value-of select  anzacDay   gt  lt br  gt                           lt xsl value-of select  christmasDay   gt  lt br  gt                           lt xsl value-of select  boxingDay   gt  lt br  gt                           lt xsl value-of select  laborDay   gt  lt br  gt                           lt xsl value-of select  easter   gt  lt br  gt                           lt xsl value-of select  queenBirthDay   gt  lt br  gt                       lt  xsl for-each gt                       lt xsl for-each select  states stateName  gt                           lt xsl value-of select  Name   gt  lt br  gt                       lt  xsl for-each gt                   lt  xsl for-each gt               lt  body gt           lt  html gt       lt  xsl template gt   lt  xsl stylesheet gt    Result   Australia Canberra English 21000000 Australian Dollar Advance Australia Fair Australia Day  26 January  Green and Gold Opal Wattle  Acacia pycnantha  1 January 26 January 25 April 25 December 26 December Variable Date Variable Date 21 April  Variable Date  NSW - New South Wales VIC - Victoria QLD - Queensland SA - South Australia WA - Western Australia TAS - Tasmania

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The default values for minOccurs and maxOccurs are 1  Thus    lt xsd element minOccurs  1  name  asdf   gt    cardinality is  1-1  Note  if you specify only minOccurs attribute  it can t be greater than 1  because the default value for maxOccurs is 1    lt xsd element minOccurs  5  maxOccurs  2  name  asdf   gt    invalid   lt xsd element maxOccurs  2  name  asdf   gt    cardinality is  1-2  Note  if you specify only maxOccurs attribute  it can t be smaller than 1  because the default value for minOccurs is 1    lt xsd element minOccurs  0  maxOccurs  0   gt    is a valid combination which makes the element prohibited   For more info see http   www w3 org TR xmlschema-0  OccurrenceConstraints

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New  expanded answer to an old  commonly asked question     Default Values   Occurrence constraints minOccurs and maxOccurs default to 1      Common Cases Explained   lt xsd element name  A   gt    means A is required and must appear exactly once      lt xsd element name  A  minOccurs  0   gt    means A is optional and may appear at most once       lt xsd element name  A  maxOccurs  unbounded   gt    means A is required and may repeat an unlimited number of times       lt xsd element name  A  minOccurs  0  maxOccurs  unbounded   gt    means A is optional and may repeat an unlimited number of times     See Also   W3C XML Schema Part 0  Primer     In general  an element is required to appear when the value of   minOccurs is 1 or more  The maximum number of times an element may   appear is determined by the value of a maxOccurs attribute in its   declaration  This value may be a positive integer such as 41  or the   term unbounded to indicate there is no maximum number of occurrences    The default value for both the minOccurs and the maxOccurs attributes   is 1  Thus  when an element such as comment is declared without a   maxOccurs attribute  the element may not occur more than once  Be sure   that if you specify a value for only the minOccurs attribute  it is   less than or equal to the default value of maxOccurs  i e  it is 0 or 1    Similarly  if you specify a value for only the maxOccurs attribute  it must be greater than or equal to the default value of minOccurs    i e  1 or more  If both attributes are omitted  the element must   appear exactly once   W3C XML Schema Part 1  Structures Second Edition    lt element   maxOccurs    nonNegativeInteger   unbounded     1   minOccurs   nonNegativeInteger   1    gt    lt  element gt

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Short answer   As written in xsd    lt xs attribute name  minOccurs  type  xs nonNegativeInteger  use  optional  default  1   gt   lt xs attribute name  maxOccurs  type  xs allNNI  use  optional  default  1   gt    If you provide an attribute with number  then the number is boundary  Otherwise attribute should appear exactly once

[xml] XML Schema minOccurs / maxOccurs default values

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Default Values

Common Cases Explained

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