Changing the table-specific identity gap  Gaps from other causes

Chapter 8: Creating Databases and Tables

Displaying table-specific identity gap information

To see the identity_gap setting for a table, use sp_help.

For example, the zero value in the identity_gap column (towards the end of the output) indicates that no table-specific identity gap is set. mytable uses the server-wide identity burning set factor value.

sp_help mytable
Name    Owner    Object_type    Create_date
------- -------- -------------- -----------------------------
mytable dbo      user table     Nov 29 2004 1:30PM

(1 row affected)
Column_name     Type   Length Prec Scale Nulls Default_name   Rule_name
        Access_Rule_name  Computed_Column_object   Identity   
--------------- --------------- ------ ---- ----- ----- --------------- 
    --------------- --------
IdNum           numeric              6   12     0     0 NULL     NULL
        NULL              NULL                              1
Object does not have any indexes.
No defined keys for this object.
name    type       partition_type   partitions   partition_keys
------- ---------- ---------------- ------------ ---------------
mytable base table roundrobin                  1 NULL

partiton_name       partition_id   pages     segment   create_date
-----------------   -------------- --------- --------- ------------------------
mytable_1136004047  1136004047            1  default     Nov 29 2004 1:30PM

partition_conditions
--------------------
NULL

Avg_pages   Max_pages   Min_pages   Ratio(Max/Avg)        Ration(Min/Avg)
----------- ----------- ----------- --------------------- -------------------
         1           1           1              1.000000                1.000000

Lock scheme Allpages
The attribute ’exp_row_size’ is not applicable to tables with 
allpages lock scheme.
The attribute ’concurrency_opt_threshold’ is not applicable to 
tables with allpages lock scheme.

exp_row_size reservepagegap fillfactor max_rows_per_page identity_gap 
 ------------ -------------- ---------- ----------------- ------------ 
            1              0          0                 0            0
concurrency_opt_threshold   optimistic_index_lock   dealloc_first_txtpg
--------------------------- ----------------------- --------------------
                        0                          0                     0
(return status = 0)

If you change the identity_gap of mytable to 20, the sp_help output for the table shows 20 in the identity_gap column. This setting overrides the server-wide identity burning set factor value.

sp_help mytable
Name    Owner    Object_type    Create_date
------- -------- -------------- -----------------------------
mytable dbo      user table     Nov 29 2004 1:30PM

(1 row affected)
Column_name     Type   Length Prec Scale Nulls Default_name   Rule_name
        Access_Rule_name  Computed_Column_object   Identity   
--------------- --------------- ------ ---- ----- ----- --------------- 
    --------------- --------
IdNum           numeric              6   12     0     0 NULL     NULL
        NULL              NULL                              1
Object does not have any indexes.
No defined keys for this object.
name    type       partition_type   partitions   partition_keys
------- ---------- ---------------- ------------ ---------------
mytable base table roundrobin                  1 NULL

partiton_name       partition_id   pages     segment   create_date
-----------------   -------------- --------- --------- ------------------------
mytable_1136004047  1136004047            1  default     Nov 29 2004 1:30PM

partition_conditions
--------------------
NULL


Avg_pages   Max_pages   Min_pages   Ratio(Max/Avg)        Ration(Min/Avg)
----------- ----------- ----------- --------------------- -------------------
         1           1           1              1.000000                1.000000
Lock scheme Allpages
The attribute ’exp_row_size’ is not applicable to tables with 
allpages lock scheme.
The attribute ’concurrency_opt_threshold’ is not applicable to 
tables with allpages lock scheme.

exp_row_size reservepagegap fillfactor max_rows_per_page identity_gap 
 ------------ -------------- ---------- ----------------- ------------
           1              0          0                 0            0
concurrency_opt_threshold   optimistic_index_lock   dealloc_first_txtpg
--------------------------- ----------------------- --------------------
                        0                          0                     0
(return status = 0) 




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