![]() ![]() To retain the identity counter, use DELETE instead.Ī TRUNCATE TABLE operation can be rolled back. If no seed was defined, the default value 1 is used. If the table contains an identity column, the counter for that column is reset to the seed value defined for the column. To remove the table definition in addition to its data, use the DROP TABLE statement. TRUNCATE TABLE removes all rows from a table, but the table structure and its columns, constraints, indexes, and so on remain. For indexes, the delete operation can leave empty pages behind, although these pages will be deallocated quickly by a background cleanup process. If the delete operation does not use a table lock, the table (heap) will contain many empty pages. ![]() ![]() For example, empty pages in a heap cannot be deallocated without at least an exclusive (LCK_M_X) table lock. Without exception, zero pages are left in the table.Īfter a DELETE statement is executed, the table can still contain empty pages. TRUNCATE TABLE always locks the table (including a schema (SCH-M) lock) and page but not each row. When the DELETE statement is executed using a row lock, each row in the table is locked for deletion. TRUNCATE TABLE removes the data by deallocating the data pages used to store the table data and records only the page deallocations in the transaction log. The DELETE statement removes rows one at a time and records an entry in the transaction log for each deleted row. RemarksĬompared to the DELETE statement, TRUNCATE TABLE has the following advantages: To truncate a partitioned table, the table and indexes must be aligned (partitioned on the same partition function). can be specified as partition numbers separated by the word TO, for example: WITH (PARTITIONS (6 TO 8)) Provide both ranges and individual partitions, for example: WITH (PARTITIONS (2, 4, 6 TO 8)) Provide the partition numbers for several individual partitions separated by commas, for example: WITH (PARTITIONS (1, 5)) Provide the number of a partition, for example: WITH (PARTITIONS (2)) If the WITH PARTITIONS clause is not provided, the entire table will be truncated. If the table is not partitioned, the WITH PARTITIONS argument will generate an error. Specifies the partitions to truncate or from which all rows are removed. WITH ( PARTITIONS ( ) )Īpplies to: SQL Server ( SQL Server 2016 (13.x) through current version) table_name cannot be the OBJECT_ID() function or a variable. Is the name of the table to truncate or from which all rows are removed. Is the name of the schema to which the table belongs. To view Transact-SQL syntax for SQL Server 2014 and earlier, see Previous versions documentation. ![]()
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