Identity Column Nearing or Reached Max

Identity columns are auto-assigned values by SQL Server and have a maximum value determined by the column type (see table below). Each time a row is inserted into the table, the identity column is assigned the next highest value. If the identity reaches the maximum value, inserts will fail.

Column Type Maximum Value
tinyint 255
smallint 32767
int 2147483647
bigint 9223372036854775807

Suggested Action

If further row inserts are expected, consider changing the column type to the next largest data type (e.g., intbigint).

How to Change Data Type in SQL Server

ALTER TABLE TableName ALTER COLUMN TextColum BIGINT;

Further Reading

int, bigint, smallint, and tinyint (Transact-SQL) | Microsoft Docs

ALTER TABLE (Transact-SQL) | Microsoft Docs