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.
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 am not sure if this has been answered before but what I found i am not sure how to make work for me but here is my problem.
I have a database used to keep track of phones for multiple clients. What needs to be done is have a query that can be ran that will run against multiple databases on the same server. each database uses the same table name that I am looking at but the names are slightly different. I came up with this..
INSERT INTO `export db`.exportinfo2
SELECT *
FROM (SELECT * FROM `export db'.tentantnames).users
WHERE name = 'Caller ID:emergency' AND value > 0
What suppose to happen is from a table that has all the database names is is to got to each database and go into the table labeled users and run a where clause on the data then export results to a different database table
I know the code needs to be dynamic but I am not sure how to make it dynamic and function. The table that has all the names for the databases is automatically created every few days.. I am not sure what else needs to be said without sounding like i repeat myself but i just need help making a dynamic query that uses a table premade as database names and run a where statement on the same named table in each database which have their name stored in a different table.
You should look into Synonyms. It can be used to fulfill your purpose
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.
I would like to recreate a few existing Access queries in a new database so that I can tweak them a bit. The problem I am running into is that some of the tables being queried do not seem to exist in the current database. These tables all end with a 1.
For example, INV_MTL_ITEM_LOCATIONS is an imported table in the database, but
INV_MTL_ITEM_LOCATIONS_1 is being queried even though it does not show up in the tables panel on the left.
Is this some type of duplication functionality that I am not aware of? The query runs without any errors.
No, the query runs on an aliased table. It's actually just querying INV_MTL_ITEM_LOCATIONS
Using SQL, you can create an alias for a table. This is especially useful when querying the same table twice in one query, but also commonly used to shorten queries.
Your query will probably look something like this:
SELECT something
FROM INV_MTL_ITEM_LOCATIONS AS INV_MTL_ITEM_LOCATIONS_1
Access automatically creates these aliases when using the query builder and if you add the same table more than once. When removing the non-aliased table, the other one stays aliased.
This is entirely normal, and as far as I know, never a problem.
Erik's answer explains it perfectly.
But to be exhaustive, you CAN actually create a query on a table that is NOT in the current database (nor a linked table).
Here is an example:
SELECT *
FROM History IN 'c:\test\mySecretBackend.accdb'
You can also create that in design view, just by
setting the query's Source Database property to c:\test\mySecretBackend.accdb
click on Show table
I'm trying to use a simple mysql database but tweak it so that every field is backed up up to an indefinite number of versions. The best way I can illustrate this is by replacing each and every field of every table with a stack of all the values this field has ever had (each of these values should be timestamped). I guess it's kind of like having customized version control for all my data..
Any ideas on how to do this?
The usual method for "tracking any changes" to a table is to add insert/update/delete trigger procedures on the table and have those records saved in a history table.
For example, if your main data table is "ItemInfo" then you would also have an ItemInfo_History table that got a copy of the new record every time anything changed (via the triggers).
This keeps the performance of your primary table consistent, yet gives you access to the history of any changes if you need it.
Here are some examples, they are for SQL Server but they demonstrate the logic:
My Repository table
My Repository History table
My Repository Insert trigger procedure
My Repository Update trigger procedure
Hmm, what you're talking about sounds similar to Slowly Changing Dimension.
Be aware that version control on arbitrary database structures is officially a rather Hard Problem. :-)
A simple solution would be to add a version/revision field to the tables, and whenever a record is updated, instead of updating it in place, insert a copy with the changes applied and the version number incremented. Then when selecting, always choose the record with the latest version. That's roughly how most such schemes are implemented (e.g. Wikimedia does it pretty much this exact way).
Maybe a tool can help you to do that for you. Have a look at nextep designer :
https://github.com/christophefondacci/nextep-designer
With this IDE you will be able to take snapshots of your database structure and data and put it under version control. After this you can compute the differences between any 2 versions and generate the appropriate SQL that can insert / update / delete your data.
Maybe this is an alternative way to achieve what you wanted.