Difference between revisions of "Update Queries"

From TRCCompSci - AQA Computer Science
Jump to: navigation, search
Line 1: Line 1:
 
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.
<br />
+
<nowiki>
  
 
Editing 'table':
 
Editing 'table':
Line 6: Line 6:
 
:"UPDATE table SET column1=value1;"                      - Sets all values in the table, in column1, to value1 (regardless of their current value).
 
:"UPDATE table SET column1=value1;"                      - 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.
 
:"UPDATE table SET column1=value1, column2=value2;"      - Changes column1 to value1 and column2 to value2.
 +
</nowiki>

Revision as of 14:46, 21 December 2016

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': :"UPDATE table SET column1=value1 WHERE column2=value2;" - 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). :"UPDATE table SET column1=value1, column2=value2;" - Changes column1 to value1 and column2 to value2.