Then empty the table (this could take some time if the table is big) : TRUNCATE TABLE table_name Ĭheck the table size again to see the changes. Description Truncate operations drop and re-create the table, which is much faster than deleting rows one by one, particularly for large tables. To get the table size in GB, execute : SELECT table_schema AS DB_NAME, TABLE_NAME, (DATA_LENGTH+INDEX_LENGTH)/1024/1024/1024 AS TABLE_SIZE_in_MB FROM information_schema.TABLES īy now you should know your database and tables size ! in order to truncate table, when still connected to the mysql prompt, execute : USE database_name Then to get the table size in MB, execute : SELECT table_name AS "Table", ROUND(((data_length + index_length) / 1024 / 1024), 2) AS "Size (MB)" FROM information_schema.TABLES WHERE table_schema = "testdb" ORDER BY (data_length + index_length) DESC Logically, the TRUNCATE TABLE statement is like a DELETE statement without a. Example DROP TABLE Shippers Try it Yourself » Note: Be careful before deleting a table. Then to get the database size in GB, execute : SELECT table_schema "database", sum(data_length + index_length)/1024/1024/1024 "size in GB" FROM information_schema.TABLES GROUP BY table_schema The MySQL TRUNCATE TABLE statement allows you to delete all data in a table. Type '\c' to clear the current input statement. Locate the database name you want to use and ensure you type that name on a single line. The USE statement in MySQL allows you to select a particular database as the default.
Server version: 10.3.13-MariaDB Source distributionĬopyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others. Step 3: Once connected to the MySQL server, select the database that contains the table you want to truncate via the USE statement. įirst connect to the server with putty, To get the databases on server and there size, execute : du -h -max-depth=1 /var/lib/mysql/Įnter the mysql prompt : # mysql -u root -p I have a stored procedure that truncates some tables with around 1.75M rows in each, before inserting new data (based on data in other tables, calculations etc.) Basic outline is very simple: Truncate Tables Insert 1.75M rows in 'batches' of around 75,000 per time. The truncate table statement is similar to delete statement without a. Now, what if we want to delete the Students table that we just truncated.Sometime swollen table in a databasecan cause disk space problem and if the data inside if expandable then you want/need to empty the table. The MySQL TRUNCATE TABLE statement allows you to delete all data in a table. The MySQL TRUNCATE TABLE statement is used to remove all records from database table.
#Mysql truncate table code#
Then go to SQL tab Place your code to truncate the table in the SQL Editor example truncate table students Replace students with the name of the table. Syntax for MySQL DROP DROP TABLE table_name Code language: SQL (Structured Query Language) ( sql ) Example of MySQL DROP The TRUNCATE TABLE statement is used when you want to delete the complete data from a table without removing the table structure. Login to PHPMYADMIN and click the table you want to truncate. It only clears the data within the table.
#Mysql truncate table how to#
As we observed, the TRUNCATE command does not delete the table by itself. The following examples show how to use TRUNCATE in the major database management systems: Oracle, SQL Server, and MySQL. Let’s move to understanding the MySQL DROP command here.
MySQL DROP – Delete MySQL Tables and Databases If you were to put an INSERT statement after this to add a record, it would work. What we can infer from this is that TRUNCATE clears all the records from the tables but does not delete the table.
Furthermore, when we use the DESCRIBE command, we can see the structure of the table. truncate table testResultTable Depending on your specific needs, if you need to get rid of the table correctly and then re-create it, you can do: drop table testResultTable create table testResultTable as select. Explanation: The items is an already existing. If you want to remove all data from the table, then your syntax is correct: truncate testResultTable or. For an InnoDB table, InnoDB processes TRUNCATE TABLE by deleting rows one by one if there are any FOREIGN KEY constraints that reference the table. As you can see, when we use the SELECT statement, we get an empty set as our output. In MySQL, the TRUNCATE TABLE statement is used to truncate or remove records of a table but not the structure.
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