Copy many tables in MySQL
I want to copy many tables with similar names but different prefixes. I want the tables with the wp_ prefix to go into their corresponding tables with the shop_ prefix.
In开发者_C百科 other words, I want to do something like this:
insert into shop_wpsc_*
select * from wp_wpsc_*
How would you do this?
SQL doesn't allow wildcarding table names - the only way to do this is to loop through a list of tables (via the ANSI INFORMATION_SCHEMA/INFORMATION_SCHEMAS) while using dynamic SQL.
Dynamic SQL is different for every database vendor...
Update
MySQL? Why didn't you say so in the first place...
MySQL's dynamic SQL is called "Prepared Statements" - this is my fav link for it besides the documentation. There're numerous questions on SO about operations on all the tables in a MySQL database - just need to tweak the WHERE clause to get the table names you want.
You'll want to do this from within a MySQL stored procedure...
You can do this by combining multiple statements into a single prepared statement -- try doing this:
SELECT @sql_text := GROUP_CONCAT(
CONCAT('insert into shop_wpsc_',
SUBSTRING(table_name, 9),
' select * from ', table_name, ';'), ' ')
FROM INFORMATION_SCHEMA.TABLES
WHERE table_schema = 'example'
AND table_name LIKE 'wp_wpsc_%';
PREPARE stmt FROM @sql_text;
EXECUTE stmt;
Expanding on OMG Ponies' answer a bit, you can use the data dictionary and write a SQL to write the SQL's. For example, in Oracle, you could do something like this:
SELECT 'insert into shop_wpsc_' || SUBSTR(table_name,9) || ' select * from ' || table_name || ';'
FROM all_tables
WHERE table_name LIKE 'WP_SPSC%'
This will generate a series of SQL statements you can run as a single script. Like OMG Ponies' pointed out though, the syntax will vary depending on what DB vendor you are using (e.g. all_tables
is Oracle specific).
First I would select all tables from the catalog views (the name of those may depend on your dmbs, though if they are ansi compatible they should support INFORMATION_SCHEMA) that start with wp_wpsc_
.
(For instance for DB2:
SELECT NAME FROM TABLES WHERE NAME LIKE 'wp_wpsc_%'
)
Then iterate through that result set, and create a dynamic statement in the form you have given to read from the current table and insert into the corresponding new one.
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