MySQL :: MySQL 8.0 Reference Manual :: 13.2.13 UPDATE Statement (2022)

13.2.13UPDATE Statement

UPDATE is a DML statement that modifies rows in a table.

An UPDATE statement can start with a WITH clause to define common table expressions accessible within the UPDATE. See Section13.2.15, “WITH (Common Table Expressions)”.

Single-table syntax:

UPDATE [LOW_PRIORITY] [IGNORE] table_reference SET assignment_list [WHERE where_condition] [ORDER BY ...] [LIMIT row_count]value: {expr | DEFAULT}assignment: col_name = valueassignment_list: assignment [, assignment] ...

Multiple-table syntax:

UPDATE [LOW_PRIORITY] [IGNORE] table_references SET assignment_list [WHERE where_condition]

For the single-table syntax, the UPDATE statement updates columns of existing rows in the named table with new values. The SET clause indicates which columns to modify and the values they should be given. Each value can be given as an expression, or the keyword DEFAULT to set a column explicitly to its default value. The WHERE clause, if given, specifies the conditions that identify which rows to update. With no WHERE clause, all rows are updated. If the ORDER BY clause is specified, the rows are updated in the order that is specified. The LIMIT clause places a limit on the number of rows that can be updated.

For the multiple-table syntax, UPDATE updates rows in each table named in table_references that satisfy the conditions. Each matching row is updated once, even if it matches the conditions multiple times. For multiple-table syntax, ORDER BY and LIMIT cannot be used.

For partitioned tables, both the single-single and multiple-table forms of this statement support the use of a PARTITION clause as part of a table reference. This option takes a list of one or more partitions or subpartitions (or both). Only the partitions (or subpartitions) listed are checked for matches, and a row that is not in any of these partitions or subpartitions is not updated, whether it satisfies the where_condition or not.

Note

Unlike the case when using PARTITION with an INSERT or REPLACE statement, an otherwise valid UPDATE ... PARTITION statement is considered successful even if no rows in the listed partitions (or subpartitions) match the where_condition.

For more information and examples, see Section24.5, “Partition Selection”.

where_condition is an expression that evaluates to true for each row to be updated. For expression syntax, see Section9.5, “Expressions”.

table_references and where_condition are specified as described in Section13.2.10, “SELECT Statement”.

You need the UPDATE privilege only for columns referenced in an UPDATE that are actually updated. You need only the SELECT privilege for any columns that are read but not modified.

The UPDATE statement supports the following modifiers:

UPDATE IGNORE statements, including those having an ORDER BY clause, are flagged as unsafe for statement-based replication. (This is because the order in which the rows are updated determines which rows are ignored.) Such statements produce a warning in the error log when using statement-based mode and are written to the binary log using the row-based format when using MIXED mode. (Bug #11758262, Bug #50439) See Section17.2.1.3, “Determination of Safe and Unsafe Statements in Binary Logging”, for more information.

If you access a column from the table to be updated in an expression, UPDATE uses the current value of the column. For example, the following statement sets col1 to one more than its current value:

UPDATE t1 SET col1 = col1 + 1;

The second assignment in the following statement sets col2 to the current (updated) col1 value, not the original col1 value. The result is that col1 and col2 have the same value. This behavior differs from standard SQL.

UPDATE t1 SET col1 = col1 + 1, col2 = col1;

Single-table UPDATE assignments are generally evaluated from left to right. For multiple-table updates, there is no guarantee that assignments are carried out in any particular order.

If you set a column to the value it currently has, MySQL notices this and does not update it.

If you update a column that has been declared NOT NULL by setting to NULL, an error occurs if strict SQL mode is enabled; otherwise, the column is set to the implicit default value for the column data type and the warning count is incremented. The implicit default value is 0 for numeric types, the empty string ('') for string types, and the zero value for date and time types. See Section11.6, “Data Type Default Values”.

If a generated column is updated explicitly, the only permitted value is DEFAULT. For information about generated columns, see Section13.1.20.8, “CREATE TABLE and Generated Columns”.

UPDATE returns the number of rows that were actually changed. The mysql_info() C API function returns the number of rows that were matched and updated and the number of warnings that occurred during the UPDATE.

You can use LIMIT row_count to restrict the scope of the UPDATE. A LIMIT clause is a rows-matched restriction. The statement stops as soon as it has found row_count rows that satisfy the WHERE clause, whether or not they actually were changed.

If an UPDATE statement includes an ORDER BY clause, the rows are updated in the order specified by the clause. This can be useful in certain situations that might otherwise result in an error. Suppose that a table t contains a column id that has a unique index. The following statement could fail with a duplicate-key error, depending on the order in which rows are updated:

UPDATE t SET id = id + 1;

For example, if the table contains 1 and 2 in the id column and 1 is updated to 2 before 2 is updated to 3, an error occurs. To avoid this problem, add an ORDER BY clause to cause the rows with larger id values to be updated before those with smaller values:

UPDATE t SET id = id + 1 ORDER BY id DESC;

You can also perform UPDATE operations covering multiple tables. However, you cannot use ORDER BY or LIMIT with a multiple-table UPDATE. The table_references clause lists the tables involved in the join. Its syntax is described in Section13.2.10.2, “JOIN Clause”. Here is an example:

UPDATE items,month SET items.price=month.priceWHERE items.id=month.id;

The preceding example shows an inner join that uses the comma operator, but multiple-table UPDATE statements can use any type of join permitted in SELECT statements, such as LEFT JOIN.

If you use a multiple-table UPDATE statement involving InnoDB tables for which there are foreign key constraints, the MySQL optimizer might process tables in an order that differs from that of their parent/child relationship. In this case, the statement fails and rolls back. Instead, update a single table and rely on the ON UPDATE capabilities that InnoDB provides to cause the other tables to be modified accordingly. See Section13.1.20.5, “FOREIGN KEY Constraints”.

You cannot update a table and select directly from the same table in a subquery. You can work around this by using a multi-table update in which one of the tables is derived from the table that you actually wish to update, and referring to the derived table using an alias. Suppose you wish to update a table named items which is defined using the statement shown here:

CREATE TABLE items ( id BIGINT NOT NULL AUTO_INCREMENT PRIMARY KEY, wholesale DECIMAL(6,2) NOT NULL DEFAULT 0.00, retail DECIMAL(6,2) NOT NULL DEFAULT 0.00, quantity BIGINT NOT NULL DEFAULT 0);

To reduce the retail price of any items for which the markup is 30% or greater and of which you have fewer than one hundred in stock, you might try to use an UPDATE statement such as the one following, which uses a subquery in the WHERE clause. As shown here, this statement does not work:

mysql> UPDATE items > SET retail = retail * 0.9 > WHERE id IN > (SELECT id FROM items > WHERE retail / wholesale >= 1.3 AND quantity > 100);ERROR 1093 (HY000): You can't specify target table 'items' for update in FROM clause

Instead, you can employ a multi-table update in which the subquery is moved into the list of tables to be updated, using an alias to reference it in the outermost WHERE clause, like this:

UPDATE items, (SELECT id FROM items WHERE id IN (SELECT id FROM items WHERE retail / wholesale >= 1.3 AND quantity < 100)) AS discountedSET items.retail = items.retail * 0.9WHERE items.id = discounted.id;

Because the optimizer tries by default to merge the derived table discounted into the outermost query block, this works only if you force materialization of the derived table. You can do this by setting the derived_merge flag of the optimizer_switch system variable to off before running the update, or by using the NO_MERGE optimizer hint, as shown here:

UPDATE /*+ NO_MERGE(discounted) */ items, (SELECT id FROM items WHERE retail / wholesale >= 1.3 AND quantity < 100) AS discounted SET items.retail = items.retail * 0.9 WHERE items.id = discounted.id;

The advantage of using the optimizer hint in such a case is that it applies only within the query block where it is used, so that it is not necessary to change the value of optimizer_switch again after executing the UPDATE.

Another possibility is to rewrite the subquery so that it does not use IN or EXISTS, like this:

UPDATE items, (SELECT id, retail / wholesale AS markup, quantity FROM items) AS discounted SET items.retail = items.retail * 0.9 WHERE discounted.markup >= 1.3 AND discounted.quantity < 100 AND items.id = discounted.id;

In this case, the subquery is materialized by default rather than merged, so it is not necessary to disable merging of the derived table.

FAQs

How do I update a MySQL statement? ›

Introduction to MySQL UPDATE statement
  1. First, specify the name of the table that you want to update data after the UPDATE keyword.
  2. Second, specify which column you want to update and the new value in the SET clause. ...
  3. Third, specify which rows to be updated using a condition in the WHERE clause.

How do I update all values in a column in MySQL? ›

To set all values in a single column MySQL query, you can use UPDATE command. The syntax is as follows. update yourTableName set yourColumnName =yourValue; To understand the above syntax, let us create a table.

How do I find the last updated column in MySQL? ›

The only way for doing this is Using something like a Log file, in this case you will create a table that will contains the updated columns each time there is an update. In this way you will be able to get the last record that will contains the table_name and the column_name.

How do I update MySQL workbench to latest version? ›

To perform an upgrade using MySQL Installer:
  1. Start MySQL Installer.
  2. From the dashboard, click Catalog to download the latest changes to the catalog. ...
  3. Click Upgrade. ...
  4. Deselect all but the MySQL server product, unless you intend to upgrade other products at this time, and click Next.
  5. Click Execute to start the download.

What is update command? ›

Update command is a data manipulation command which is used to edit the records of a table. It may be used to update a single row based on a condition, all rows or set of rows based on the condition given by the user.

What is update query with example? ›

The SQL UPDATE Query is used to modify the existing records in a table. You can use the WHERE clause with the UPDATE query to update the selected rows, otherwise all the rows would be affected.

How do you update data in a database? ›

The UPDATE statement changes existing data in one or more rows in a table.
...
SQL UPDATE syntax
  1. First, specify the table name that you want to change data in the UPDATE clause.
  2. Second, assign a new value for the column that you want to update. ...
  3. Third, specify which rows you want to update in the WHERE clause.

What is select for update in MySQL? ›

A SELECT ... FOR UPDATE reads the latest available data, setting exclusive locks on each row it reads. Thus, it sets the same locks a searched SQL UPDATE would set on the rows.

How do you update all rows in a column in SQL? ›

Syntax: UPDATE table_name SET column_name1 = new_value1, column_name2 = new_value2 ---- WHERE condition; Here table_name is the name of the table, column_name is the column whose value you want to update, new_value is the updated value, WHERE is used to filter for specific data.

How can I tell when a MySQL table was last updated? ›

SELECT UPDATE_TIME FROM information_schema. tables WHERE TABLE_SCHEMA = 'yourDatabaseName' AND TABLE_NAME = 'yourTableName'; Let us implement the following query to get the last updated time. mysql> SELECT UPDATE_TIME -> FROM information_schema.

How do I get latest data in SQL? ›

In SQL Server, we can easily select the last 10 records from a table by using the “SELECT TOP” statement. The TOP clause in SQL Server is used to control the number or percentage of rows from the result. And to select the records from the last, we have to arrange the rows in descending order.

How can I tell when a SQL table was last updated? ›

If a user wants to find out when was the last table updated he can query dynamic management view (DMV) – sys. dm_db_index_usage_stats and easily figure out when was the table updated last.

Should I upgrade MySQL 8? ›

MySQL 8.0 has important performance and security improvements, and, as in all migration to a new database version, there are several things to take into account before going into production to avoid hard issues like data loss, excessive downtime, or even a rollback during the migration task.

What is the latest version of MySQL? ›

This version contains the releases of MySQL 5.7 to MySQL 5.6. 27 versions. This version contains the releases of MySQL 8.0 to MySQL 8.0.
...
Features Removed in MySQL 8.0.
Old NameNew Name
INNODB_SYS_TABLESTATSINNODB_TABLESTATS
INNODB_SYS_VIRTUALINNODB_VIRTUAL
8 more rows

How do I update my workbench? ›

To upgrade your workbench, you need to build additional structures next to it. Each of the following must be built near the workbench. To find your workbench upgrades, open the crafting menu and navigate to the Crafting tab. Each new item that upgrades your workbench will be labeled as a workbench improvement.

How do you update a query? ›

On the Design tab, in the Query Type group, click Update. This procedure shows you how to change a select query to an update query. When you do this, Access adds the Update to row in the query design grid.

Which type of command is update? ›

UPDATE Command is a Data Manipulation Language (DML). Alter command will perform the action on structure level and not on the data level. Update command will perform on the data level. ALTER Command is used to add, delete, modify the attributes of the relations (tables) in the database.

What is update statement? ›

In SQL, the UPDATE statement is used to modify or update existing records in a table. You can use it to update everything all at once, or you can specify a subset of records to modify using the WHERE clause. The UPDATE statement is considered a SQL data manipulation command.

What is update syntax in SQL? ›

An SQL UPDATE statement changes the data of one or more records in a table. Either all the rows can be updated, or a subset may be chosen using a condition. The UPDATE statement has the following form: UPDATE table_name SET column_name = value [, column_name = value ...] [ WHERE condition]

How do I update two values in SQL? ›

UPDATE table_name SET column1 = value1, column2 = value2,... WHERE condition; table_name: name of the table column1: name of first , second, third column.... value1: new value for first, second, third column.... condition: condition to select the rows for which the values of columns needs to be updated.

How can I update two rows at a time in SQL? ›

There are a couple of ways to do it. INSERT INTO students (id, score1, score2) VALUES (1, 5, 8), (2, 10, 8), (3, 8, 3), (4, 10, 7) ON DUPLICATE KEY UPDATE score1 = VALUES(score1), score2 = VALUES(score2);

What is database update? ›

The modification of data that is already in the database is referred to as updating. You can update individual rows, all the rows in a table, or a subset of all rows. Each column can be updated separately; the other columns are not affected.

How do you create an update query in Access? ›

How to Create Update Queries in Access
  1. Click the Create tab on the ribbon.
  2. Click the Query Design button. ...
  3. Double-click the tables and queries you want to add and click Close. ...
  4. Click the Update button. ...
  5. Click the Update To row for the field you want to update and type an expression. ...
  6. Click the Run button. ...
  7. Click Yes.

How do you insert and update a single query in SQL? ›

Sql Insert Select Update Code Along
  1. Use the INSERT INTO command to insert data (i.e. rows) into a database table.
  2. Use SELECT statements to select data from a database table.
  3. Use the WHERE Clause to select data from specific table rows.
  4. Use comparison operators, like < or > , to select specific data.

How do I use update and SELECT together in SQL? ›

  1. Select update. update P1 set Name = P2.Name from Product P1 inner join Product_Bak P2 on p1.id = P2.id where p1.id = 2.
  2. Update with a common table expression. ; With CTE as ( select id, name from Product_Bak where id = 2 ) update P set Name = P2.name from product P inner join CTE P2 on P.id = P2.id where P2.id = 2.
  3. Merge.

What is the use of SELECT for update? ›

The SELECT FOR UPDATE statement is used to order transactions by controlling concurrent access to one or more rows of a table. It works by locking the rows returned by a selection query, such that other transactions trying to access those rows are forced to wait for the transaction that locked the rows to finish.

How do I check MySQL version? ›

Windows users can employ PowerShell or the command prompt and Linux and MacOS have the Terminal. To check the version your MySQL is running, type and execute mysql -V (note the uppercase V) in the command line. As you can see, the MySQL version for this system is 10.4. 12.

How can I update 100 rows in SQL? ›

UPDATE TOP (100) table_name set column_name = value; If you want to show the last 100 records, you can use this if you need. Show activity on this post. The TOP qualifier can also be used as limit the the number of rows manually updated incorrectly.

How do you update a specific column in SQL? ›

Now, we are going to explain each step with an example:
  1. Step 1: Create a Database. ...
  2. Step 2: Create a Table and Insert the data. ...
  3. Step 3: View the Table before updating the values. ...
  4. Step 4: Change the value of a particular column in the table. ...
  5. Step 5: View the Table after updating the values.

How can I update one column to another column in the same table in SQL? ›

In such a case, you can use the following UPDATE statement syntax to update column from one table, based on value of another table. UPDATE first_table, second_table SET first_table. column1 = second_table. column2 WHERE first_table.id = second_table.

How do I know if my database is updated? ›

You can use $stmt->rowCount() to find out if any rows were updated. It will be 0 if no rows were found, otherwise it will be non-zero. However, this will also return 0 if rows were found but there was nothing to change, because the value of logged is already the new value you tried to assign.

How can I see all table status in MySQL? ›

You can also get this list using the mysqlshow --status db_name command. The LIKE clause, if present, indicates which table names to match.
...
SHOW TABLE STATUS output has these columns:
  1. Name. The name of the table.
  2. Engine. The storage engine for the table. ...
  3. Version. ...
  4. Row_format. ...
  5. Rows. ...
  6. Avg_row_length. ...
  7. Data_length. ...
  8. Max_data_length.

How do I find recently updated rows in SQL Server? ›

To get the last updated record in SQL Server: We can write trigger (which automatically fires) i.e. whenever there is a change (update) that occurs on a row, the “lastupdatedby” column value should get updated by the current timestamp.

How do I get last 10 rows in SQL? ›

mysql> SELECT * FROM ( -> SELECT * FROM Last10RecordsDemo ORDER BY id DESC LIMIT 10 -> )Var1 -> -> ORDER BY id ASC; The following is the output that displays the last 10 records.

How do I get last 3 records in SQL? ›

This one-liner is the simplest query in the list, to get the last 3 number of records in a table. The TOP clause in SQL Server returns the first N number of records or rows from a table. Applying the ORDER BY clause with DESC, will return rows in descending order. Hence, we get the last 3 rows.

How do I get the first and last record of a table in SQL? ›

To get the first and last record, use UNION. LIMIT is also used to get the number of records you want.

How can I tell who modified a table in SQL Server? ›

In order to find out who update the table, you could try with below options:
  1. Try and read the Transaction Logs to see what happened.
  2. Start trace in SQL Server profiler and checked events(TSQL-SQL:BatchCompleted,SQL:BatchStarting,SQL:StmtCompleted and SQL:StmtStarting)(Recommended).
15 Nov 2020

How do I find the last modified column in SQL Server? ›

Solution. Using a SQL Server trigger to check if a column is updated, there are two ways this can be done; one is to use the function update(<col name>) and the other is to use columns_updated().

How do I find the last modified view in SQL Server? ›

If you need to find out which tables have been recently modified. You can check this by querying the sys. tables in TSQL based on the modify_date column.

Can you run two versions of MySQL? ›

It is possible to use a different MySQL server binary per instance, or use the same binary for multiple instances, or any combination of the two approaches. For example, you might run a server from MySQL 5.7 and one from MySQL 8.0, to see how different versions handle a given workload.

What is in-place upgrade in MySQL? ›

An in-place upgrade involves shutting down the old MySQL server, replacing the old MySQL binaries or packages with the new ones, restarting MySQL on the existing data directory, and upgrading any remaining parts of the existing installation that require upgrading.

Is MySQL still supported? ›

The latest version of MySQL is supported until April 2026 and keeps your database features up to date with continuously receiving updates and fixes, especially the security patches.

Is MySQL 8.0 stable? ›

So if you are using one user for your client, it won't be a problem and is more secure than the previous versions. Since MySQL leverages the most up-to-date hardware and software, it changes its default variables. You can read here for more details. Overall, MySQL 8.0 has dominated MySQL 5.7 efficiently.

Why did MySQL jump to version 8? ›

"Due to the many new and important features we were introducing in this MySQL version, we decided to start a fresh new series. As the series numbers 6 and 7 had actually been used before by MySQL, we went to 8.0."

What is difference between SQL and MySQL? ›

SQL is a query programming language that manages RDBMS. MySQL is a relational database management system that uses SQL. SQL is primarily used to query and operate database systems. MySQL allows you to handle, store, modify and delete data and store data in an organized way.

Why update is not working in MySQL? ›

You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column To disable safe mode, toggle the option in Preferences -> SQL Editor and reconnect.

How do I update a database in MySQL Workbench? ›

Following is a generic syntax of UPDATE command to modify data into the MySQL table:
  1. UPDATE table_name.
  2. SET column_name1 = new-value1,
  3. column_name2=new-value2, ...
  4. [WHERE Clause]

How do I change MySQL version in workbench? ›

2. Open "Edit" > "Preferences" > "Modeling" > "MySQL" and look for "Default target MySQL Version" ---- Or see https://github.com/mysql/mysql-workbench/blob/8.0.11/plugins/db.mysql/backend/db_plugin_be... and confirm "5.6. 30" is hard-coded. Suggested fix: Change "5.6.

How do you update a database query? ›

Open the database that contains the records you want to update. On the Create tab, in the Queries group, click Query Design. Click the Tables tab. Select the table or tables that contain the records that you want to update, click Add, and then click Close.

How do you update data in a database? ›

The UPDATE statement changes existing data in one or more rows in a table.
...
SQL UPDATE syntax
  1. First, specify the table name that you want to change data in the UPDATE clause.
  2. Second, assign a new value for the column that you want to update. ...
  3. Third, specify which rows you want to update in the WHERE clause.

Can I update primary key in MySQL? ›

To change the primary key of a table, delete the existing key using a DROP clause in an ALTER TABLE statement and add the new primary key. Note You must be logged in to the database using a database name before you can add a primary key or conduct any other referential integrity (RI) operation.

Which of the following commands will you use to update values in a? ›

Answer: UPDATE command is used to update any record of data in a table.

How do you update and in SQL? ›

UPDATE Syntax

Notice the WHERE clause in the UPDATE statement. The WHERE clause specifies which record(s) that should be updated. If you omit the WHERE clause, all records in the table will be updated!

Which SQL statement is used to update data in a database? ›

The UPDATE statement in SQL is used to update the data of an existing table in database. We can update single columns as well as multiple columns using UPDATE statement as per our requirement. UPDATE table_name SET column1 = value1, column2 = value2,...

What is an update query access? ›

An Update Query is an action query (SQL statement) that changes a set of records according to criteria (search conditions) you specify.

How does SQL update work? ›

The basic SQL UPDATE syntax comes down to using keyword UPDATE followed by the name of our object (table or table alias) and the SET column name equals to some values. The FROM clause will come into play when we do joins and we can also have a WHERE clause when we need to update only a portion of data in a table.

How do you update all rows in a column in SQL? ›

Syntax: UPDATE table_name SET column_name1 = new_value1, column_name2 = new_value2 ---- WHERE condition; Here table_name is the name of the table, column_name is the column whose value you want to update, new_value is the updated value, WHERE is used to filter for specific data.

How do you update a record in a table? ›

The UPDATE command in SQL is used to modify or change the existing records in a table. If we want to update a particular value, we use the WHERE clause along with the UPDATE clause. If you do not use the WHERE clause, all the rows will be affected.

Can primary key be updated? ›

Short answer: yes you can.

How do I set primary key in MySQL? ›

The syntax to create a primary key using the CREATE TABLE statement in MySQL is: CREATE TABLE table_name ( column1 column_definition, column2 column_definition, ... CONSTRAINT [constraint_name] PRIMARY KEY [ USING BTREE | HASH ] (column1, column2, ... column_n) );

How do I change the primary key value of a column in SQL Server? ›

But, if you really need to, you can do the following:
  1. Disable enforcing FK constraints temporarily (e.g. ALTER TABLE foo WITH NOCHECK CONSTRAINT ALL )
  2. Then update your PK.
  3. Then update your FKs to match the PK change.
  4. Finally enable back enforcing FK constraints.

Can I update 2 columns in SQL? ›

We can update multiple columns by specifying multiple columns after the SET command in the UPDATE statement. The UPDATE statement is always followed by the SET command, it specifies the column where the update is required.

What is safe update mode in MySQL? ›

MySQL has a safe update mode to prevent administrators from issuing an UPDATE or DELETE statement without a WHERE clause. You can see if safe update mode is enabled in your MySQL server by checking the global variable sql_safe_updates .

Which type of command is update? ›

UPDATE Command is a Data Manipulation Language (DML). Alter command will perform the action on structure level and not on the data level. Update command will perform on the data level. ALTER Command is used to add, delete, modify the attributes of the relations (tables) in the database.

Top Articles

Latest Posts

Article information

Author: Tyson Zemlak

Last Updated: 12/08/2022

Views: 5601

Rating: 4.2 / 5 (43 voted)

Reviews: 90% of readers found this page helpful

Author information

Name: Tyson Zemlak

Birthday: 1992-03-17

Address: Apt. 662 96191 Quigley Dam, Kubview, MA 42013

Phone: +441678032891

Job: Community-Services Orchestrator

Hobby: Coffee roasting, Calligraphy, Metalworking, Fashion, Vehicle restoration, Shopping, Photography

Introduction: My name is Tyson Zemlak, I am a excited, light, sparkling, super, open, fair, magnificent person who loves writing and wants to share my knowledge and understanding with you.