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admin:indexing:indexes:groups [2011/01/21 00:49]
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admin:indexing:indexes:groups [2016/06/28 22:38] (current)
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 {{page>:​top_add&​nofooter&​noeditbtn}} {{page>:​top_add&​nofooter&​noeditbtn}}
  
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 ==== Index Groups ==== ==== Index Groups ====
  
-Index Groups are used to combine multiple indexes into one single index. ​ This allows a search against any one index within the group to automatically search all indexes within the group. ​ For example, if a table has three lines, ADDRESS_LINE_1,​ ADDRESS_LINE_2 and ADDRESS_LINE_3,​ they can be indexed as an Index Group. ​ Criteria against any one of those three columns will automatically search all address lines.+Index Groups are used to combine multiple indexes into one single index. ​ This allows a search against any one index within the group to automatically search all indexes within the group. ​ For example, if a table has three lines, ADDRESS_LINE_1,​ ADDRESS_LINE_2and ADDRESS_LINE_3,​ they can be indexed as an Index Group. ​ Criteria against any one of those three columns will automatically search all address lines.
  
 In the example below, a row displays an address: In the example below, a row displays an address:
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 If these three columns are added to an Index Group, then the following search will locate the row: If these three columns are added to an Index Group, then the following search will locate the row:
  
 +<​code>​
   select ​       NAME, ADDRESS_LINE_1,​ ADDRESS_LINE_2,​ ADDRESS_LINE_3   select ​       NAME, ADDRESS_LINE_1,​ ADDRESS_LINE_2,​ ADDRESS_LINE_3
     from        CUSTOMERS     from        CUSTOMERS
     where       ​ADDRESS_LINE_1 = '1254 Broadway, Yonkers, NY'     where       ​ADDRESS_LINE_1 = '1254 Broadway, Yonkers, NY'
 +</​code>​
  
 Care should be taken when considering where to use Index Groups. ​ When indexes are combined into an Index Group, they lose the ability to distinguish which column originally contained the values. ​ This can lead to confusion. ​ For example, the following search will also locate the row: Care should be taken when considering where to use Index Groups. ​ When indexes are combined into an Index Group, they lose the ability to distinguish which column originally contained the values. ​ This can lead to confusion. ​ For example, the following search will also locate the row:
  
 +<​code>​
   select ​       NAME, ADDRESS_LINE_1,​ ADDRESS_LINE_2,​ ADDRESS_LINE_3   select ​       NAME, ADDRESS_LINE_1,​ ADDRESS_LINE_2,​ ADDRESS_LINE_3
     from        CUSTOMERS     from        CUSTOMERS
     where       ​ADDRESS_LINE_1 = '10710 Yonkers Street Suite 100'     where       ​ADDRESS_LINE_1 = '10710 Yonkers Street Suite 100'
 +</​code>​
  
 === Common Uses of Index Groups === === Common Uses of Index Groups ===
  
-Index Groups can be used in many different situations. ​ Here is a little of common situation where Index Groups are used:+Index Groups can be used in many different situations. ​ Here is a common situation where Index Groups are used:
  
   * Combining indexes for multiple address lines   * Combining indexes for multiple address lines
   * Combining indexes for a short-description column and a long-description column.   * Combining indexes for a short-description column and a long-description column.
-  * Combining indexes for given names, nicknames and aliases+  * Combining indexes for given names, nicknamesand aliases
   * Combining indexes for multiple telephone numbers   * Combining indexes for multiple telephone numbers
   * Combining indexes for multiple email addresses   * Combining indexes for multiple email addresses
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 If HOUSEHOLDS.HOME_PHONE and INDIVIDUALS.MOBILE_PHONE were added to an Index Group, then this household would be returned in the following query. ​ Note that the query searches the indexes in the INDIVIDUALS table **even though the INDIVIDUALS table is not referenced in the query.**  ​ If HOUSEHOLDS.HOME_PHONE and INDIVIDUALS.MOBILE_PHONE were added to an Index Group, then this household would be returned in the following query. ​ Note that the query searches the indexes in the INDIVIDUALS table **even though the INDIVIDUALS table is not referenced in the query.**  ​
  
 +<​code>​
   select ​       HOUSEHOLD, ADDRESS, CITY, STATE, ZIP   select ​       HOUSEHOLD, ADDRESS, CITY, STATE, ZIP
     from        HOUSEHOLDS     from        HOUSEHOLDS
     where       ​HOME_PHONE = '720 298 3162'     where       ​HOME_PHONE = '720 298 3162'
 +</​code>​
  
-As discussed above, care should be taken when considering where to use Index Groups across tables. ​ It can be confusing ​that when a table is searched without it being included ​in the SQL statement. ​ A row can also be qualified when a portion of the criteria exists in the parent and another portion exists in a child row.  For example, the following search will also locate this household:+As discussed above, care should be taken when considering where to use Index Groups across tables. ​ It can be confusing when a table is actually ​searched without it being referenced ​in the SQL statement. ​ A row can also be qualified when a portion of the criteria exists in the parent and another portion exists in a child row.  For example, the following search will also locate this household:
  
 +<​code>​
   select ​       HOUSEHOLD, ADDRESS, CITY, STATE, ZIP   select ​       HOUSEHOLD, ADDRESS, CITY, STATE, ZIP
     from        HOUSEHOLDS     from        HOUSEHOLDS
     where       ​HOME_PHONE = '303 298 2238'     where       ​HOME_PHONE = '303 298 2238'
 +</​code>​
  
-Because of this characteristic,​ Index Groups are best suited for Omnidex Indexes, ​or QuickText Indexes containing free-form text where the location of keywords is not material.  Index Groups also work well when combining columns with data that is so different it would never lead to confusion.+Because of this characteristic,​ Index Groups are best suited for a) Omnidex Indexes, ​b)  ​QuickText Indexes containing free-form text where the location of keywords is not material, or c) combinations of indexes where the data between columns ​is so different it would not be confused.
  
 ====  ====  ====  ==== 
 
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