I have to compare two database tables and fields ( Not their DATA) .
Say Live DB and Development DB. In live DB there are 200 tables and
in development DB there are 218 Tables With some new column fields
added in old tables too.
During the final stage i have to update the Live DB by adding the new
columns and tables taken from the development DB .
I should not loss and data in the old DB.
I tried many ways to do this but it is taking a very long time for me
to finish. One of the tool i used is mysql workbench.
Is there any queries to perform this using information schema ?
To make the things easier i imported the development DB from development server and uploaded in the live db with different name . Now both the DB are in the same server but with diff name. E.g. sitedb , sitedevdb
Whenever you update the development DB with changes that will eventually be put live, you should write a .sql script that will repeat the changes on the live database.
Otherwise this operation is super-tricky.. you may have to manually figure out the added columns yourself, or you may be able to use each INFORMATION_SCHEMA.COLUMNS to compare the old tables.
For the new tables SHOW CREATE **table_name** is really useful.
A MySQL comparison tool is probably what you need for this. The company I work for, Redgate, offers MySQL Compare (for the database schema) and MySQL Data Compare (for data).
These tools are free for non-commercial use.
I have two database, each contain different tables
leave.sql and crm.sql
I want to transfer all my leave tables into the crm database
How should I do it?
If the other database has different tables then the leaves database then all you need to do is import the data into the crm database. Finally, make sure your leaves script is connected to the new crm database.
Two other methods:
On the mysql prompt, you can rename your tables - and effectively move them from one database to the other (if both are on the same filesystem):
From http://dev.mysql.com/doc/refman/5.0/en/rename-table.html:
As long as two databases are on the same file system, you can use
RENAME TABLE to move a table from one database to another:
RENAME TABLE current_db.tbl_name TO other_db.tbl_name;
If you are using MyISAM tables, and you have root privileges, you can just do:
stop your mysql server
move your tables from the old database directory to the new one
start your mysql server
All those assuming the tables in your old database (the ones you want to move) have different names than the ones in your new database (the ones you want to keep). If that's not true, you'll also have to change the names.
I have inserted new columns in one database, and I now want to add the same type of columns to a second database. I need to know which columns are in the first database that are not in the second. I have many tables in each database that needs column difference comparing. I searched the web and I can only find ways to see the difference of the contents of columns in two tables. I don't need to compare the contents, just different columns in all the tables in each database. Each database has the same tables.
Thanks!
I found that you can do a database dump that just has the structure from phpmyadmin.
Are you doing this manually? You could just use SHOW CREATE to see the structure of the tables, and then something like the diff command in Linux to compare them.
For a commercial product answer: I use Red Gate's SQL Compare which works great. It can compare the entire schema of two databases. It can also update your target database to match your source database.
Use redgate SQL compare to comapre schema of two tables.
sql-dbdiff works well too. Its an open source.
We are handling a data aggregation project by having several microsoft sql server databases combining to one mysql database. all mssql database have the same schema.
The requirements are :
each mssql database can be imported to mysql independently
before being able to import each record to mysql we need to validates each records with a specific createrias via php.
each imported mssql database can be rollbacked. It means even it already imported to mysql, all the mssql database can be removed from the mysql.
we would still like to know where does each record imported to the mysql come from what mssql database.
All import process will be done with PHP .
we have difficulty in many aspects. we don't know what is the best approach to solve our problem.
your help will be highly appreciated.
ps: each mssql database has around 60 tables and each table can have a few hundred thousands .
Don't use PHP as a database administration utility. Any time you build a quick PHP script to transfer records directly from one database to another, you're going to cause yourself a world of hurt when that script becomes required for production operation.
You have a number of problems that you need solved:
You have multiple MSSQL databases with similar if not identical tables.
You have a single MySQL database that you want to merge the data into.
The imported data must be altered in a specific way before being merged.
You want to prevent all duplicate records in your import.
You want to know what database each record originally came from.
The solution?
Analyze the source MSSQL databases and create a merge strategy for them.
Create a database structure on the MySQL database that fits the merge strategy in #1, including all the new key constraints (like unique and foreign keys) required for the consolidation.
At this point you have two options left:
Dump the data from each of the source databases into raw data using your RDBMS administration utility of choice. Alter that data to fit your merge strategy and constraints. Document this, and then merge all of the data into your new database structure.
Use a tool like opendbcopy to map columns from one database to another and run a mass import.
Hope this helps.
If I have a MySQL database with several tables on a live server, now I would like to migrate this database to another server. Of course, the migration I mean here involves some database tables, for example: add some new columns to several tables, add some new tables etc..
Now, the only method I can think of is to use some php/python(two scripts I know) script, connect two databases, dump the data from the old database, and then write into the new database. However, this method is not efficient at all. For example: in old database, table A has 28 columns; in new database, table A has 29 columns, but the extra column will have default value 0 for all the old rows. My script still needs to dump the data row by row and insert each row into the new database.
Using MySQLDump etc.. won't work. Here is the detail. For example: I have FOUR old databases, I can name them as 'DB_a', 'DB_b', 'DB_c', 'DB_d'. Now the old table A has 28 columns, I want to add each row in table A into the new database with a new column ID 'DB_x' (x to indicate which database it comes from). If I can't differentiate the database ID by the row's content, the only way I can identify them is going through some user input parameters.
Is there any tools or a better method than writing a script yourself? Here, I dont need to worry about multithread writing problems etc.., I mean the old database will be down (not open to public usage etc.., only for upgrade ) for a while.
Thanks!!
I don't entirely understand your situation with the columns (wouldn't it be more sensible to add any new columns after migration?), but one of the arguably fastest methods to copy a database across servers is mysqlhotcopy. It can copy myISAM only and has a number of other requirements, but it's awfully fast because it skips the create dump / import dump step completely.
Generally when you migrate a database to new servers, you don't apply a bunch of schema changes at the same time, for the reasons that you're running into right now.
MySQL has a dump tool called mysqldump that can be used to easily take a snapshot/backup of a database. The snapshot can then be copied to a new server and installed.
You should figure out all the changes that have been done to your "new" database, and write out a script of all the SQL commands needed to "upgrade" the old database to the new version that you're using (e.g. ALTER TABLE a ADD COLUMN x, etc). After you're sure it's working, take a dump of the old one, copy it over, install it, and then apply your change script.
Use mysqldump to dump the data, then echo output.txt > msyql. Now the old data is on the new server. Manipulate as necessary.
Sure there are tools that can help you achieving what you're trying to do. Mysqldump is a premier example of such tools. Just take a glance here:
http://dev.mysql.com/doc/refman/5.1/en/mysqldump.html
What you could do is:
1) You make a dump of the current db, using mysqldump (with the --no-data option) to fetch the schema only
2) You alter the schema you have dumped, adding new columns
3) You create your new schema (mysql < dump.sql - just google for mysql backup restore for more help on the syntax)
4) Dump your data using the mysqldump complete-insert option (see link above)
5) Import your data, using mysql < data.sql
This should do the job for you, good luck!
Adding extra rows can be done on a live database:
ALTER TABLE [table-name] ADD [row-name] MEDIUMINT(8) default 0;
MySql will default all existing rows to the default value.
So here is what I would do:
make a copy of you're old database with MySql dump command.
run the resulting SQL file against you're new database, now you have an exact copy.
write a migration.sql file that will modify you're database with modify table commands and for complex conversions some temporary MySql procedures.
test you're script (when fail, go to (2)).
If all OK, then goto (1) and go live with you're new database.
These are all valid approaches, but I believe you want to write a sql statement that writes other insert statements that support the new columns you have.