Oracle Big Table cleanup truncate... reuse storage
Recently, a large table needs to be cleaned up, which requires no impact on performance. In MySQL, we can minimize I/O by using coreutils and hard links. Oracle can also minimize I/O by recycling space in batches. What is the problem.
1. truncate
Myth #19: TRUNCATE TABLE operations are not logged to the log
Error
Actions in the user table are recorded in the log. The only operation in SQL Server that is not logged to the log is row versioning in tempdb.
The Truncate table statement deletes all data from the enti
TRUNCATE table deletes all rows in a table without recording a single row delete operation.
GrammarTRUNCATE TABLE name;ParametersName (the names of the tables you want to truncate or the names of the tables whose rows you want to delete)
First, syntax in SQL1. Thedrop table name eg:drop table dbo. Sys_test2.truncate table name eg:truncate table dbo. Sys_test3.Delete from table name where Column name = value Eg:delete from dbo. Sys_test where test= ' Test 'Secon
Label:First, syntax in SQL 1. Thedrop table name eg:drop table dbo. Sys_test2.truncate table name eg:truncate table dbo. Sys_test3.Delete from table name where column name = value Eg:delete from dbo. Sys_test where test= ' Test
The difference between delete and truncate: delete generates rollback. If you delete a table with a large amount of data, it will take up a lot of rollback segments. truncate is a DDL operation and does not generate rollback, which is faster.
Oracle Clearing table SQL statement and difference between
TRUNCATE TABLE Name
Nameis the name of the table that you want to truncate or the name of the table for which you want to delete all rows.TRUNCATE table is functionally the same as a DELETE statement without a WHERE clause: Both d
Misunderstanding #19: operations on the Truncate table will not be loggedErrorOperations in the User table are recorded in logs. The only operation in SQL Server that is not logged is row Version Control in TempDB.The Truncate Table statement deletes all data in the entire
Refer to others summary, this content only for oneself studyI. Syntax in SQL1.drop Table name Eg:drop table dbo. Sys_test2.truncate Table name eg:truncate table dbo. Sys_test3.delete from table name where column name = value Eg:de
Delete all rows in the table without recording the delete operation of a single row. The TRUNCATETABLE function is the same as the DELETE statement without a WHERE clause. However, the TRUNCATETABLE is faster and less system resources and transaction log resources are used.
Delete all rows in the table without recording the delete operation of a single row. The truncate
TRUNCATE TABLE
Syntax
TRUNCATE TABLEName
Delete all rows in the table without recording the delete operation of a single row.
The truncate table function is the same as the DELETE statement without the WHERE clause: both DEL
I have read some related posts and articles on the Internet, which are basically the same, but there are some differences in some places. Here I will summarize the differences between the two.
1.
Delete generates rollback and related lock information. If you delete a table with a large data volume, it takes up a lot of rollback segments. truncate is a DDL operation and does not generate rollback.
Tags: import use hang share picture DMI lag ref page ToolWhen TRUNCATE table occurs, how to recover, I believe most people will choose to restore the backup to TRUNCATE table before, and then re-import the data into the formal table.So in SQL Server is not really only this method, of course, this is the content of this
Tags: truncate TABLEThe DELETE statement in SQL deletes one or more records from the table, and you can provide a WHERE clause to the DELETE statement, and any conditions that can be used in the SELECT statement in SQL can be used in the delect WHERE clause. The syntax format for the DELETE statement is:DELETE [from] {table_name|view_name} [WHERE condition].If you do not specify a WHERE clause for the DELET
Label:There are two ways to delete data in MySQL, one is a DELETE statement and the other is a TRUNCATE TABLE statement. The DELETE statement can select the record to be deleted by where. Using TRUNCATE TABLE will delete all records in the table. Therefore, the DELETE statem
Oracle empty table SQL statements and truncate and delete differences
TRUNCATE TABLE [name]
Remove or cluster all rows from the table using the TRUNCATE statement. By default, the Oracle Database tutorial also performs the fo
TRUNCATE TABLEDeletes all rows in the table without logging a single row delete operation.GrammarTRUNCATE TABLE NameParametersNameis the name of the table to truncate or the table whose entire row you want to delete.CommentsTRUNCA
TRUNCATE TABLEDeletes all rows in the table without logging a single row delete operation.GrammarTRUNCATE TABLEnameParametersNameis the name of the table to truncate or the table whose entire row you want to delete.CommentsTRUNCATE table
For some large tables, it is better to use truncate table to delete data than delete data. Truncate table (TRANSACT-SQL)
Removes all rows from a table without logging the individual row deletions. truncate
To remove all rows from a table, the TRUNCATE table statement is a quick and efficient method. TRUNCATE TABLE is similar to a DELETE statement that does not contain a WHERE clause. However, TRUNCATE
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