Progress
SQL-92
Guide and Reference
CREATE INDEX Statement
Creates an index on the specified table using the specified columns of the table. An index improves the performance of SQL operations whose predicates are based on the indexed column. However, an index slows performance of INSERT, DELETE, and UPDATE operations.
SYNTAX
UNIQUE
Does not allow the table to contain any rows with duplicate column values for the set of columns specified for that index.
index_name
Must be unique within the local database.
table_name
The name of the table on which the index is being built.
column_name [ , ... ]
The columns on which searches and retrievals will be ordered. These columns are called the index key. When more than one column is specified in the
CREATE INDEX
statement, a concatenated index is created.area_name
The name of the storage area where the index and its entries are stored.
ASC | DESC
Allows the index to be ordered as either ascending (
ASC
) or descending (DESC
) on each column of the concatenated index. The default isASC
.NOTES
EXAMPLEThis example illustrates how to create a UNIQUE INDEX on a table:
AUTHORIZATION
Must have DBA privilege or INDEX privilege on the table.
SQL COMPLIANCE
ODBC Core SQL grammar
ENVIRONMENT
Embedded SQL, interactive SQL, ODBC applications, JDBC applications
RELATED STATEMENTS
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