I need to dump a table for daily transfer.
mysqldump requires LOCK TABLES privilege. Unfortunately, LOCK TABLES does not apply at the table level, only at the database level, and I don't want to give the MySQL user that much access.
Is there a way to do something like ...
/usr/bin/mysql -uusername -ppassword -D daterbase -e "select * from table" > outfile.sql
... but have it output in SQL format instead of query result format?
If the table is an InnoDB table, you can use mysqldump --single-transaction dbname tablename.
By using a transaction, it doesn't need to lock anything.
Or you can use SELECT ... INTO OUTFILE but that dumps in a tab-delimited text format, not in SQL format. See on mysql for details.
Related
I need to restore a dumped database, but without discarding existing rows in tables.
To dump I use:
mysqldump -u root --password --databases mydatabase > C:\mydatabase.sql
To restore I do not use the mysql command, since it will discard all existing rows, but instead mysqlimport should do the trick, obviously. But how? Running:
mysqlimport -u root -p mydatabase c:\mydatabase.sql
says "table mydatabase.mydatabase does not exist". Why does it look for tables? How to restore dump with entire database without discarding existing rows in existing tables? I could dump single tables if mysqlimport wants it.
What to do?
If you are concerned with stomping over existing rows, you need to mysqldump it as follows:
MYSQLDUMP_OPTIONS="--no-create-info --skip-extended-insert"
mysqldump -uroot --ppassword ${MYSQLDUMP_OPTIONS} --databases mydatabase > C:\mydatabase.sql
This will do the following:
remove CREATE TABLE statements and use only INSERTs.
It will INSERT exactly one row at a time. This helps mitigate rows with duplicate keys
With the mysqldump performed in this manner, now you can import like this
mysql -uroot -p --force -Dtargetdb < c:\mydatabase.sql
Give it a Try !!!
WARNING : Dumping with --skip-extended-insert will make the mysqldump really big, but at least you can control each duplicate done one by one. This will also increase the length of time the reload of the mysqldump is done.
I would edit the mydatabase.sql file in a text editor, dropping the lines that reference dropping tables or deleting rows, then manually import the file normally using the mysql command as normal.
mysql -u username -p databasename < mydatabase.sql
The mysqlimport command is designed for dumps created with the mysql command SELECT INTO OUTFILE rather than direct database dumps.
This sounds like it is much more complicated than you are describing.
If you do a backup the way you describe, it has all the records in your database. Then you say that you do not want to delete existing rows from your database and load from the backup? Why? The reason why the backup file (the output from mysqldump) has the drop and create table commands is to ensure that you don't wind up with two copies of your data.
The right answer is to load the mysqldump output file using the mysql client. If you don't want to do that, you'll have to explain why to get a better answer.
How do I remove selective tables from a MySQL dump. I would like to remove the following tables from my dump file. How should I do this.
"DATABASECHANGELOG", "DATABASECHANGELOGLOCK",
I guess you could take a mysqldump using the following command to ignore the specific tables on making dump , so you could step away from risks of removing the tables after taking the dump
mysqldump -u username -p database_name --ignore-table=database_name.table1 --ignore-table=database_name.table2 > test.sql
I'm regularly running mysqldump against a Drupal database and man, those cache tables can get huge. Considering that the first thing I do after reloading the data is clear the cache, I'd love it if I could just skip dumping all those rows altogether. I don't want to skip the table creation (with --ignore-tables), I just want to skip all those rows of cached data.
Is it possible to tell mysqldump to dump the CREATE TABLE statement skip the INSERT statements for a specific set of tables?
There is a --no-data option that does this, but it affects all tables AFAIK. So, you'll have to run mysqldump twice.
# Dump all but your_special_tbl
mysqldump --ignore-table=db_name.your_special_tbl db_name > dump.sql
# Dump your_special_tbl without INSERT statements.
mysqldump --no-data db_name your_special_tbl >> dump.sql
You have to call mysqldump twice.
The mysql-stripped-dump script does exactly this.
I'd like to be able to make a backup of tables with less than 100K rows. What I'm trying to do is clone a development database to my local machine that has many log tables that I don't need the data for, and tables with "legitimate" content.
So I'm going to have one dump that just copies the structures of the tables, and another, that copies the relevant data from these tables with less than 100k rows.
If I have to use an intermediary language like Python or PHP, I'm fine with that.
edit: So the question is, how do I create a mysql dump of data from tables with less than 100k rows?
USe something like this
mysql databasename -u [root] -p[password] —disable-column-names -e
'select table_name from information_schema.tables where table_rows < 100000;'
| xargs mysqldump [databasename] -u [root] -p[password] > [target_file]
p.s. all this will need to be in a single line
To dump only the schema
mysqldump --user=dbuser --password --no-data --tab=/tmp dbname
or try to export schema and data seperately for each table with below command
mysqldump --user=dbuser --password --tab=/tmp dbname
Or
mysqldump --opt --where="1 limit 100000" database > fileName.sql
that would give you the 100K rows from every table.
To Ignore some tables
mysqldump --opt --where="1 limit 100000" --ignore-table=database.table1
--ignore-table=database.table2 database > fileName.sql
Is there any application that will read a MySQL database table and generate a SQL script of INSERT statements (so that I can copy tables from one db to another db)? OR how can I transfer content from db1.table1 to db2.table2 where table1 and table2 is same.
Thank you.
mysqldump [options] db_name [tbl_name ...]
Will generate the script file including the create and inserts necessary for the tables selected. To import the dump you can simply do:
mysql -u <user> -p dbname < mys.dmp
You should take a look at mysqldump. You can specify the --nodata option to export the schema only.