25,134 Metrics install automatically if you have Redgate Monitor installed.
If you are using Redgate’s SQL Server monitoring tool, Redgate Monitor, you can instantly install and run this metric on your servers.
If your application relies on identity columns, use this metric to measure the number of identity columns that are near to the limit per database. If an identity column is getting close to the limit of the datatype, you need to know so that you can avoid logical problems in your application and SQL Server errors. For example, if you created an IDENTITY column of smallint datatype, if you try to insert more than 32767 rows in the table, you will get the following error:
Server: Msg 8115, Level 16, State 1, Line 1
Arithmetic overflow error converting IDENTITY to data type smallint. Arithmetic overflow occurred.
This is a limitation of the datatype, not the identity.
For more information, see http://vyaskn.tripod.com/sql_server_check_identity_columns.htm
If you want to carry out further analysis, run this query to find which tables have the identity column near to the limit:
[sql]WITH CTE_1
AS
(
SELECT OBJECT_NAME(a.Object_id) as table_name,
a.Name as columnname,
CONVERT(bigint, ISNULL(a.last_value,0)) AS last_value,
Case
When b.name = ‘tinyint’ Then 255
When b.name = ‘smallint’ Then 32767
When b.name = ‘int’ Then 2147483647
When b.name = ‘bigint’ Then 9223372036854775807
End As dt_value
FROM sys.identity_columns a
INNER JOIN sys.types As b
ON a.system_type_id = b.system_type_id
),
CTE_2
AS
(
SELECT *,
CONVERT(Numeric(18,2), ((CONVERT(Float, last_value) / CONVERT(Float, dt_value)) * 100)) AS "Percent"
FROM CTE_1
)
SELECT *
FROM CTE_2
ORDER BY "Percent" DESC; [/sql]
Metric definition
Name
Identity columns near limit
Description
This metric measures the number of identity columns that are near to the limit per database. If an identity column is getting close to the limit of the datatype, you need to know so that you can avoid logical problems in your application and SQL Server errors. For example, if you created an IDENTITY column of smallint datatype, if you try to insert more than 32767 rows in the table, you will get the following error:
Server: Msg 8115, Level 16, State 1, Line 1
Arithmetic overflow error converting IDENTITY to data type smallint. Arithmetic overflow occurred.
This is a limitation of the datatype, not the identity.
For more information, see http://vyaskn.tripod.com/sql_server_check_identity_columns.htm
If you want to carry out further analysis, run this query to find which tables have the identity column near to the limit:WITH CTE_1
AS (SELECT OBJECT_NAME(a.Object_id) AS table_name,
a.Name AS columnname,
CONVERT(BIGINT, ISNULL(a.last_value, 0)) AS last_value,
CASE WHEN b.name = 'tinyint' THEN 255
WHEN b.name = 'smallint' THEN 32767
WHEN b.name = 'int' THEN 2147483647
WHEN b.name = 'bigint' THEN 9223372036854775807
END AS dt_value
FROM sys.identity_columns a
INNER JOIN sys.types AS b
ON
a.system_type_id = b.system_type_id
),
CTE_2
AS (SELECT *,
CONVERT(NUMERIC(18, 2), ((CONVERT(FLOAT, last_value)
/ CONVERT(FLOAT, dt_value)) * 100)) AS "Percent"
FROM CTE_1
)
SELECT *
FROM CTE_2
ORDER BY "Percent" DESC;
The T-SQL query that will collect data
Instances to collect from
Select all
Databases to collect from
1
Collection frequency
86400
Use collected or calculated values
Leave the Use a calculated rate of change between collections check box unchecked
Metric collection
Enabled
Alert definition
Alert name
Identity columns near limit
Description
This alert is raised if an identity column is getting close to the limit of the datatype. You need to know about this so you can avoid logical problems in your application and SQL Server errors. For example, if you created an IDENTITY column of smallint datatype, if you try to insert more than 32767 rows in the table, you will get the following error:
Server: Msg 8115, Level 16, State 1, Line 1
Arithmetic overflow error converting IDENTITY to data type smallint. Arithmetic overflow occurred.
This is a limitation of the datatype, not the identity.
For more information, see http://vyaskn.tripod.com/sql_server_check_identity_columns.htm
If you want to carry out further analysis, run this query to find which tables have the identity column near to the limit:WITH CTE_1
AS (SELECT OBJECT_NAME(a.Object_id) AS table_name,
a.Name AS columnname,
CONVERT(BIGINT, ISNULL(a.last_value, 0)) AS last_value,
CASE WHEN b.name = 'tinyint' THEN 255
WHEN b.name = 'smallint' THEN 32767
WHEN b.name = 'int' THEN 2147483647
WHEN b.name = 'bigint' THEN 9223372036854775807
END AS dt_value
FROM sys.identity_columns a
INNER JOIN sys.types AS b
ON
a.system_type_id = b.system_type_id
),
CTE_2
AS (SELECT *,
CONVERT(NUMERIC(18, 2), ((CONVERT(FLOAT, last_value)
/ CONVERT(FLOAT, dt_value)) * 100)) AS "Percent"
FROM CTE_1
)
SELECT *
FROM CTE_2
ORDER BY "Percent" DESC; Raise an alert when the metric value goes
Above the defined threshholds
Default threshold values
| High: | 10 |
| Medium: | 5 |
| Low: | 0 |
Note: These thresholds are intended as guideline values. If they seem too high or too low in your environment, replace them with values more suited to your server performance.
Raise an alert when the threshold is passed for
1 collection
Alert is
Enabled
