Mysql updating multiple tables

My SQL UPDATE multiple columns My SQL UPDATE command can be used to update multiple columns by specifying a comma separated list of column_name = new_value.

Where column_name is the name of the column to be updated and new_value is the new value with which the column will be updated.

Do you have any suggestions for how to work around this?

In this article I’ve shown you how to use subqueries to work around limitations on multi-table statements, and then I demonstrated how an alternate way to rewrite the query performs about 250 times better on a small data set than the obvious solution.

The following My SQL statement will update pub_lang column with NULL if purch_price is more than 50.

In this statement, other columns are also updated with respective new values.

mysql updating multiple tables-59mysql updating multiple tables-25

This may help explain the occasional deadlock we get on this table (see my article about a “little-known” way to cause a deadlock).Fluency with SQL is necessary for effective communication with the My SQL server, because that is the language that it understands.For example, when you use a program such as the mysql client, it functions primarily as a means for you to send SQL statements to the server to be executed.PHP Script Sample Output: Multiple Updates in My SQL Sample table: table1 Problem If you want to update the val1 with 5,8 and 7 for concerned id 1,3 and 4 and the other val1 will remain same and the val2 will be updated with 13 and 5 for the concerned id 2 and 4 and the other will remain same, the following update statement can be used by using IF and CASE.Code: FROM book_mast; -------- ------------------------------------ --------- ---------- | book_id| book_name | pub_lang|book_price| -------- ------------------------------------ --------- ---------- | BK001 | Introduction to Electrodynamics | English | 85.00| | BK002 | Understanding of Steel Construction| English | 105.50| | BK003 | Guide to Networking | Hindi | 200.00| | BK004 | Transfer of Heat and Mass | English | 250.00| | BK005 | Conceptual Physics | NULL | 145.00| | BK006 | Fundamentals of Heat | German | 112.00| | BK007 | Advanced 3d Graphics | Hindi | 56.00| | BK008 | Human Anatomy | German | 50.50| | BK009 | Mental Health Nursing | English | 145.00| | BK010 | Fundamentals of Thermodynamics | English | 225.00| | BK011 | The Experimental Analysis of Cat | French | 95.00| | BK012 | The Nature of World | English | 88.00| | BK013 | Environment a Sustainable Future | German | 100.00| | BK014 | Concepts in Health | NULL | 180.00| | BK015 | Anatomy & Physiology | Hindi | 135.00| | BK016 | Networks and Telecommunications | French | 45.00| -------- ------------------------------------ --------- ---------- 16 rows in set (0.00 sec) and My SQL FROM purchase; --------- ---------- ------------- ------------ | book_id | pub_lang | purch_price | total_cost | --------- ---------- ------------- ------------ | BK001 | English | 75.00 | 1125.00 | | BK004 | English | 55.00 | 440.00 | | BK005 | NULL | 20.00 | 400.00 | | BK004 | English | 35.00 | 525.00 | | BK001 | English | 25.00 | 200.00 | | BK003 | Hindi | 45.00 | 900.00 | --------- ---------- ------------- ------------ 6 rows in set (0.02 sec) If we want to update the book_price of the table book_mast by an increment of 5% and also update the purch_price and total_cost of puchase table by an increment of 5%, and this increment will affect only those rows in both book_mast and purchase table, which publishing language is English and book_id matching in both the tables, we can write the following code - UPDATE book_mast,purchase SET book_mast.book_price=book_mast.book_price (book_mast.book_price*.05), purchase.purch_price=purchase.purch_price (purchase.purch_price*.05), purchase.total_cost=receive_qty*(purchase.purch_price (purchase.purch_price*.05)) WHERE book_mast.book_id=purchase.book_id AND purchase.pub_lang="English"; FROM book_mast; -------- ------------------------------------ --------- ---------- | book_id| book_name | pub_lang|book_price| -------- ------------------------------------ --------- ---------- | BK001 | Introduction to Electrodynamics | English | 89.25| | BK002 | Understanding of Steel Construction| English | 105.50| | BK003 | Guide to Networking | Hindi | 200.00| | BK004 | Transfer of Heat and Mass | English | 262.50| | BK005 | Conceptual Physics | NULL | 145.00| | BK006 | Fundamentals of Heat | German | 112.00| | BK007 | Advanced 3d Graphics | Hindi | 56.00| | BK008 | Human Anatomy | German | 50.50| | BK009 | Mental Health Nursing | English | 145.00| | BK010 | Fundamentals of Thermodynamics | English | 225.00| | BK011 | The Experimental Analysis of Cat | French | 95.00| | BK012 | The Nature of World | English | 88.00| | BK013 | Environment a Sustainable Future | German | 100.00| | BK014 | Concepts in Health | NULL | 180.00| | BK015 | Anatomy & Physiology | Hindi | 135.00| | BK016 | Networks and Telecommunications | French | 45.00| -------- ------------------------------------ --------- ---------- 16 rows in set (0.01 sec) and My SQL FROM purchase; --------- ---------- ------------- ------------ | book_id | pub_lang | purch_price | total_cost | --------- ---------- ------------- ------------ | BK001 | English | 78.75 | 1181.25 | | BK004 | English | 57.75 | 462.00 | | BK005 | NULL | 20.00 | 400.00 | | BK004 | English | 36.75 | 551.25 | | BK001 | English | 26.25 | 210.00 | | BK003 | Hindi | 45.00 | 900.00 | --------- ---------- ------------- ------------ 6 rows in set (0.08 sec) My SQL: Update with Join Statement Sample tables Problem If we want to update the aval1of table11 with the bval1 of table12 against the following condition - 1).In order to do this, each process tries to update some rows so table or not.The query to claim a set of rows for a process needs to update the ten highest-priority unclaimed rows for eligible clients., neither of which is supported for multiple-table UPDATE in My SQL.This article explains how to do it anyway, and shows how to rewrite a first attempt for hundreds of times better performance. Selector .selector_input_interaction .selector_input. Selector .selector_input_interaction .selector_spinner. We often use join clauses to query rows in a table that have (in the case of INNER JOIN) or may not have (in the case of LEFT JOIN) corresponding rows in another table.

Leave a Reply

Your email address will not be published. Required fields are marked *

One thought on “mysql updating multiple tables”