Difference between revisions of "Update Queries"

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{| class="wikitable"
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|-
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| "UPDATE table SET column1=value1 WHERE column2=value2;" || Example
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|-
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| "UPDATE table SET column1=value1;" || Example
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|-
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| "UPDATE table SET column1=value1, column2=value2;" || Example
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|}
 
For updating values already entered into a database. Can edit multiple rows at once.  Not using the WHERE clause will cause every entry to be edited.
 
For updating values already entered into a database. Can edit multiple rows at once.  Not using the WHERE clause will cause every entry to be edited.
  
  
 
Editing 'table'
 
Editing 'table'
:"UPDATE table SET column1=value1 WHERE column2=value2;" --- Changes values in column1 to value1, where column2 equals value2.
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: --- Changes values in column1 to value1, where column2 equals value2.
:"UPDATE table SET column1=value1;"                     --- Sets all values in the table, in column1, to value1 (regardless of their current value).
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:                      --- Sets all values in the table, in column1, to value1 (regardless of their current value).
:"UPDATE table SET column1=value1, column2=value2;"     --- Changes column1 to value1 and column2 to value2.
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:      --- Changes column1 to value1 and column2 to value2.

Revision as of 15:49, 21 December 2016

"UPDATE table SET column1=value1 WHERE column2=value2;" Example
"UPDATE table SET column1=value1;" Example
"UPDATE table SET column1=value1, column2=value2;" Example

For updating values already entered into a database. Can edit multiple rows at once. Not using the WHERE clause will cause every entry to be edited.


Editing 'table'

--- Changes values in column1 to value1, where column2 equals value2.
--- Sets all values in the table, in column1, to value1 (regardless of their current value).
--- Changes column1 to value1 and column2 to value2.