My problem:
I am trying to delete some important rows from multiple tables, around 20 tables, I am afraid that deleting the rows might cause some problem(I am not the creator of this website), so before deleting the rows I am selecting the rows and writing it into a file. But I write it as an array.
Is there a way to write it as an sql insert statement, to a file, so that it would be easy for me to update the database if there is some problem.
For me it would be easier to store the information in a way that would allow me to understand the data. Then IF I need it, I could mutate the data into an INSERT statement.
I strongly encourage you as a professional software engineer, to try not to solve a problem that you might encounter, until you DO encounter it.
If you use phpMyAdmin you can run a query that selects those rows, then click the Export link under Query results operations:
In the next page, select Custom - display all possible options and SQL Format:
Then, further down the page, select data under Format specific options:
And then press Go. You will be prompted to Save or Open a file, which will include the appropriate INSERT statements to recreate the data from those rows.
Related
So I'm kind of stumped.
I have a MySql project that involves a database table that is being manipulated and altered by scripts on a regular basis. This isn't so unusual, but I need to automate a script to run (after hours, when changes aren't happening) that would save the result of the following:
SHOW CREATE TABLE [table-name];
This command generates the ready-to-run script that would create the (empty) table in it's current state.
In SqlWorkbench and Navicat it displays the result of this SHOW command in a field in a result set, as if it was the result of a SELECT statement.
Ideally, I want to take into a variable in a procedure, and change the table name; adding a '-mm-dd-yyyy' to end of it, so I could show the day-to-day changes in the table schema on an active server.
However, I can't seem to be able to do that. Unlike a Select result set, I can't use it like that. I can't get it in a variable, or save it to a temporary, or physical table or anything. I even tried to return this as a value in a function, from which I got the error that a function cannot return a result set - which explains why it's displayed like one in the db clients.
I suspect that this is a security thing in MySql? If so, I can totally understand why and see the dangers exposed to a hacker, but this isn't a public-facing box at all, and I have full root/admin access to it. Hopefully somebody has already tackled this problem before.
This is on MySql 8, btw.
[Edit] After my first initial comments, I need to add; I'm not concerned about the data with this question whatsoever, but rather just these schema changes.
What I'd really -like- to do is this:
SELECT `Create Table` FROM ( SHOW CREATE TABLE carts )
But this seems to be mixing apples and oranges, as SHOW and SELECT aren't created equal, although they both seem to return the same sort of object
You cannot do it in the MySQL stored procedure language.
https://dev.mysql.com/doc/refman/8.0/en/show.html says:
Many MySQL APIs (such as PHP) enable you to treat the result returned from a SHOW statement as you would a result set from a SELECT; see Chapter 29, Connectors and APIs, or your API documentation for more information. In addition, you can work in SQL with results from queries on tables in the INFORMATION_SCHEMA database, which you cannot easily do with results from SHOW statements. See Chapter 26, INFORMATION_SCHEMA Tables.
What is absent from this paragraph is any mention of treating the results of SHOW commands like the results of SELECT queries in other contexts. There is no support for setting a variable to the result of a SHOW command, or using INTO, or running SHOW in a subquery.
So you can capture the result returned by a SHOW command in a client programming language (Java, Python, PHP, etc.), and I suggest you do this.
In theory, all the information used by SHOW CREATE TABLE is accessible in the INFORMATION_SCHEMA tables (mostly TABLES and COLUMNS), but formatting a complete CREATE TABLE statement is a non-trivial exercise, and I wouldn't attempt it. For one thing, there are new features in every release of MySQL, e.g. new data types and table options, etc. So even if you could come up with the right query to produce this output, in a couple of years it would be out of date and it would be a thankless code maintenance chore to update it.
The closest solution I can think of, in pure MySQL, is to regularly clone the table structure (no data), like so:
CREATE TABLE backup_20220618 LIKE my_table;
As far as I know, to get your hands on the full explicit CREATE TABLE statement, as a string, would require the use of an external tool like mysqldump which was designed specifically for that purpose.
I'm a java dev who uses Mysql Workbench as a database client and IntelliJ IDEA as an IDE. Every day I do SQL queries to the database from 5 up to 50 times a day.
Is there a convenient way to save and re-run frequently used queries in Mysql Workbench/IntelliJ IDEA so that I can:
avoid typing a full query which has already been used again
smoothly access a list of queries I've already used (e.g by auto-completion)
If there is no way to do it using Mysql Workbench / IDEA, could you please advise any good tools providing this functionality?
Thanks!
Create Stored Procedures, one per query (or sequence of queries). Give them short names (to avoid needing auto-completion).
For example, to find out how many rows in table foo (SELECT COUNT(*) FROM foo;).
One-time setup:
DELIMITER //
CREATE PROCEDURE foo_ct
BEGIN;
SELECT COUNT(*) FROM foo;
END //
DELIMITER ;
Usage:
CALL foo_ct();
You can pass arguments in in order to make minor variations. Passing in a table name is somewhat complex, but numbers of dates, etc, are practical and probably easy.
If you have installed SQLyog for your mysql then you can use Favorites menu option in which you can save your query and in one click it will automatically writes the saved query on Query Editor.
The previous answers are correct - depending on the version of the Query Browser they are either called Favorites or Snippets - the problem being you can't create sub-folders to group them. And keeping tabs open is an option - but sometimes the browser 'dies' - and you're back to ground 0. So the obvious solution I came up with - create a database table! I have a few 'metadata' fields for descriptions - the project a query is associated to; problem the query solves; and the actual query.
You could keep your query library in an SQL file and load that when WB opens (it's automatically opened when you restart WB and that file was open on last close). When you want to run a specific query place the caret in it's text and press Ctrl+Enter (Cmd+Enter on Mac) to run only this query. The organization of that SQL file is totally up to you. You have more freedom than any "favorites" solution can give you. You can even have more than one file with grouped statements.
Additionally, MySQL Workbench has a query history (see the Output Tab), which is saved to disk, so you can return to a query even month's after you wrote it.
I am trying to become familiar with Magento and I want to know what tables get effected when I perform certain actions, like: creating a category, adding a product and adding shopping cart and catalog rules, etc.
Just wondering, is there a MySQL command that can tell my what tables have been effected? Something like: SELCT affected tables FROM db WHERE last updated > date.
When you run UPDATE in a MySQL console, it will tell you how many rows were modified. I belive INSERT does the same.
Libraries that allow you to modify MySQL from your code will frequently return the number of rows that were affected, although that obviously depends on what library you are using.
I'm pretty sure that's the extent of what it will tell you and that there is no such feature to tell you about what TABLES were affected. However, INSERT and UPDATE only affect one table at a time so if you can find the query in the code that is getting run, that is your best bet to find what tables are being modified.
I exported a couple of entries from a database I have stored locally on my MySQL dbase through PhpMyAdmin and I'd like to replace only those entries on my destination database hosted online. Unfortunately when I try to do so PHPMyAdmin says that those posts already exist and therefore he can't erase them.
It'll take me a lot of time to search for those entries manually within the rest of the posts and delete them one at a time so I was wondering if there's any workaround in order to overwite those entries on import.
Thanks in advance!
A great option is to handle this on your initial export from phpMyAdmin locally. When exporting from phpMyAdmin:
Export method: Custom
Format: SQL
Format-specific options - choose "data" (instead of "structure" or "structure and data")
In Data creation options - Function to use when dumping data: Switch "Insert" to "Update" <-- This is the ticket!
Click Go!
Import into your production database. (always backup your production database before hand just in case)
I know this is an old post, but it actually helped me find a solution built into phpMyAdmin. Hope it helps someone else!
This is a quick and dirty way to do it. Others may have a better solution:
It sounds like you're trying to run INSERT queries, and phpMyAdmin is telling you they already exist. If you use UPDATE queries, you could update the info.
I would copy the queries you have there, into a text editor, preferably one that can handle find and replace, like Notepad++ or Gedit, and then replace some code to change the queries around from INSERT to UPDATE.
See: http://dev.mysql.com/doc/refman/5.0/en/update.html
OR, you could just delete them, then run your INSERT queries.
You might be able to use some logic with find and replace to make a DELETE query that gets rid of them first.
http://dev.mysql.com/doc/refman/5.0/en/delete.html
Check out insert on duplicate. You can either add the syntax to your entries stored locally, or import into a temporary database, then run an INSERT ... SELECT ... ON DUPLICATE KEY UPDATE. If you could post a schema, it would help us guide you better.
I'm trying to most efficiently manage a database table and get rid of old entries that will never be accessed. Yes they could probably easily be persisted for many years but I'd just like to get rid of them. I could do this maybe once every month. Would it be more efficient to copy the entries I want to keep into a new table then simply delete the old table. Or should a query manually delete each entry after that threshhold that I set.
I'm using MySQL with JPA/JPQL JEE6 with entity annotations and Java persistence manager.
Thanks
Another solution is to design the table with range or list PARTITIONING, and then you can use ALTER TABLE to drop or truncate old partitions.
This is much quicker than using DELETE, but it may complicate other uses of the table.
A single delete query will be the most efficient solution.
Copying data from one database to another can be lengthy if you have a lot of data to keep. It means you have to retrieve all the data with a single query (or multiple, if you want to batch), and issue a lot of insert statements in the other database.
Using JPQL, you can issue a single query to delete all old statements, something like
DELETE FROM Entity e WHERE e.date = ?
This will translated to a single SQL query, and the database will take care of deleting all the unwanted records.