Difference between revisions of "KEY Table Constraint"
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A constraint is used to define rules that help to provide data integrity. TABLE constraints apply to table-based operations. You must have ALTER privilege on the table. The table will be locked for EXCLUSIVE use during the operation. | A constraint is used to define rules that help to provide data integrity. TABLE constraints apply to table-based operations. You must have ALTER privilege on the table. The table will be locked for EXCLUSIVE use during the operation. | ||
| − | The KEY table constraint is used to define an index key. The index is built on the column or columns specified and given the name as defined in <cTagName>. The INDEX table constraint can be used in the same way. | + | The KEY table constraint is used to define an index key. The index is built on the column or columns specified and given the name as defined in <cTagName>. The [[INDEX_Table_Constraint|INDEX]] table constraint can be used in the same way. |
==Example== | ==Example== | ||
<code lang="recital"> | <code lang="recital"> | ||
| − | + | CREATE TABLE contact; | |
| − | CREATE TABLE contact (LastName char(25), FirstName char(25), | + | (LastName char(25), FirstName char(25),; |
| − | KEY FullName (LastName, FirstName)) | + | KEY FullName (LastName, FirstName)) |
</code> | </code> | ||
==Products== | ==Products== | ||
| − | Recital | + | Recital, Recital Server |
[[Category:Documentation]] | [[Category:Documentation]] | ||
[[Category:SQL]] | [[Category:SQL]] | ||
Latest revision as of 10:39, 22 December 2009
Purpose
Table constraint to define an index key
Syntax
KEY [<cTagName>] (column1[, column2,...])
See Also
ALTER TABLE, CONSTRAINTS, CREATE TABLE
Description
A constraint is used to define rules that help to provide data integrity. TABLE constraints apply to table-based operations. You must have ALTER privilege on the table. The table will be locked for EXCLUSIVE use during the operation.
The KEY table constraint is used to define an index key. The index is built on the column or columns specified and given the name as defined in <cTagName>. The INDEX table constraint can be used in the same way.
Example
CREATE TABLE contact; (LastName char(25), FirstName char(25),; KEY FullName (LastName, FirstName))
Products
Recital, Recital Server
