draw database schema online

Tags: www sch contains lan Linux usr hang strong andPick to: This paper describes the problemof MySQL DDL , thept-online-schema-change of the work principle , and the actual use of The pt-online-schema-change tool modifies the 160 million-level data table structure on-line in the production environment. in a software

effective, for other types is not necessarily oh. For example: decimal The advantage is that you need to lock the table only when the Copy table structure 2. Adopt Percona tool to deal with Execute a statement that modifies a table Mysql> ALTER TABLE test1 add column nickname varchar (a) default ';Query OK, 0 rows affected (12.33 sec)records:0 duplicates:0 warnings:0 Can see the operation time is still a little long, after all, I only have 1 million data, and the table structure is simple. For

DDL (such as modifying the data type), you can Post-Test MeasurementWhether to use this tool to execute ddl SQL. pt-online-schema-change can be used to execute ALTER statements without blocking write operations on database tables. 1. Principles The table must have a primary key or a unique index !!Assume that the existing tbosc requires the ALTER operation. When

Tags: from center consumer replica csdn original database table ICT catOriginal: SQL Server updatable subscription data online schema change (add field) scenarioThe reason for the inconsistency between conflicting and subscription data has been found before, and the number of database upgrades that have been discovered

only be read and not written when InnoDB executes the DDL. To this end perconal introduced a tool pt-online-schema-change, which is characterized by the modification process will not cause read and write blocking.Working principle:If a table has a foreign key, the tool is not executed unless a specific value is specified by using –alter-foreign-keys-method.1 Create an empty table structure that is the same

wins '--4. Newly released copy schema change: false (Publication property) EXEC sp_changepublication @ Publication = n ' temp02 ', @property = N ' replicate_ddl ', @value = 0EXEC sp_changepublication @publication = n ' temp03 ', @prop Erty = N ' Replicate_ddl ', @value = 0--5. Create a subscription (subscriber new database)--6. Change the job owner, initialize 4 subscriptions, wait for completion ...--7. P

It is said that the Pt-online-schema-change in the Pt-toolkit toolset can modify the table structure on-line without locking the table, so what is the specific principle of this tool, please see below to explain:Restrictions on the use of 1.pt-online-schema-change tools:1) If the modified table has a foreign key, the t

new table, and the default action is to drop the original During copy data, any update to the original table will be updated to the new table because the tool will create a trigger on the original table, and the trigger will update the content updated on the original table to the new table. If a trigger is already defined in the table, the tool will not work. Usage Description: Pt-online-schema-change [OPT

trigger will be created, whenever the deletion of the original table and add and change operations, will trigger the corresponding operation of the new table. So there can be no other trigger on the original table, that is, if there is a trigger on the original table, the OSC will strike2. Foreign keyForeign keys make the table operation more complex, if the original table has foreign keys, automatic rename of the original table and the operation of the new table will not be smooth, you have to

MySQL performance tuning and Architecture design--9th chapter The performance optimization of MySQL database schema designPreface: Many people think that performance is optimized in the process of writing code (program code or database code), in fact, this is a very big misunderstanding. The real impact of the most performance of the part is in the design has bee

ado| Schema | data | Database use Ado.net to get database schema information Autumn Maple 2004-7-3 At the time of development, it is sometimes necessary to obtain database schema information to get some other information about t

must be operational database of each schema (room) right, That is, each database mapping user has a key to each Schema (room), in other words, if he is the owner of a warehouse, then the use of the warehouse and everything in the warehouse is his (including the room), he has the full operation right, can throw away th

and the initial mode list is empty.4. Click Add to view a complete list of available database connection modes.Note : The add operation attempts to connect to the database and retrieve all the schema lists.Mode details5. From the full list of database schemas, select the connection you want to manage the mode, and the

of a variety of common architectures, the rest is how to choose the right architecture to use in a real-world production environment. In this respect everyone has their own ideas and experience, the specific plan is the best of opinion. In the daily work of the structure of the perfect is not an overnight, but a constantly evolving process of optimization and improvement. A push in the database also experienced from a single point to master-slave to

background separation" architecture should be usedUser foreground side, "establishing non-UID attribute mapping relationship to UID" best practice:Index Table method: The mapping relation of record Login_name->uid in databaseCache mapping Method: the mapping relationship of record login_name->uid in cacheLogin_name Generating UIDLogin_name gene into UIDOperating background side, "foreground and background separation" best practices:Front desk, back-end system web/service/db decoupling, avoid ba

libraries index btree,hash Full-text index aggregation operation database meta Information Databasemeta Data ,information schema Database link gc prevents deadlocks Synchronization of database structure and data Atitit. Custom JDBC Drive Execution plan atitit. Cross-language

Original: Visual Studio2017 database schema comparisonFirst, prefaceDevelopment time on the test server and the network server has our database, when we modify or add some fields on the online network, the database of the network needs to be updated, this time according to t

Tags: Forget clear add target personal gadget important online imagesFirst, prefaceDevelopment time on the test server and the network server has our database, when we modify or add some fields on the online network, the database of the network needs to be updated, this time according to the table modification records,

When I register the sqlserver2000 script generated in the sql2005 database in the query Analyzer of the remote database and run the website, an error is found: The 'System. web. security. sqlroleprovider 'requires a database schema compatible with schema version '1 '.

Traps in the 4.2MySQL schema design Because the MySQL implementation mechanism causes some specific errors, how to avoid them, and slowly: 1. Too many columns The MySQL storage Engine API works by copying data in a row-buffered format at the server layer and storage engine layer, then decoding the buffered content into columns at the server layer, and converting the encoded columns from row buffers into rows of data is expensive . The MyISAM fixed-le