-612   identifier IS A DUPLICATE NAME

A non-unique name was specified where a unique name is required. Column and period names must be unique within an index, a table, or a view, and in the UPDATE OF clause of a trigger definition.

identifier

The non-unique name.

Possible causes for this error include:

CREATE INDEX and ALTER INDEX statements

• The same column name is specified for two or more columns of the index.

CREATE TABLE and ALTER TABLE statements

• The same column name is specified for two or more columns of the table.
• A constraint specifies an XML column and the constraint definition contains an expression that invokes the XMLQUERY function or uses the XMLEXISTS predicate.
• The same period name is specified for two or more columns of the table.
• The same period is specified more than one time in the constraint.
• A period and a column are defined with the same name.
• For a CREATE TABLE statement, a column list of a PRIMARY KEY, FOREIGN KEY, or UNIQUE clause contains two or more occurrences of the same column name.
• A column is specified more than once in an ALTER TABLE statement. With only one exception, a column cannot be specified in multiple clauses of an ALTER TABLE statement. The exception is when the two clauses are ALTER COLUMN and ADD CHECK CONSTRAINT.

CREATE VIEW statements

• The same column name is specified for two or more columns of the view

CREATE TRIGGER statements

• For a CREATE TRIGGER statement, the UPDATE OF clause specifies the same column name more than once.

XMLQUERY function or XMLEXISTS predicate

• The PASSING clause of an XMLQUERY function or an XMLEXISTS predicate contains two arguments with the same name.
• An XMLQUERY or XMLEXISTS argument list contains two arguments with the same name.

SQL data change statements

• The SQL data change statement uses an include column, and the column name that is specified is the same as another column name of the target table or view, or of another include column.