I want to name my Alias titles using data from my tables. Here's a totally stupid example to show what I want to do:
SELECT id AS CONCAT('id_', name)
Which would give me the output id_5 => 5. (if ID was 5 in the table)
Sounds like what you're after is a pivot - you mean that for each row in the table, you would end up with a new column, right? If so, then just google mysql pivot (sorry, I'm used to sqlserver)
Related
based on my question, I have a table named tbl_programme. That table has 3 columns which are ID, session, and class. Now, I want to create an MYSQL query for a PHP website that can display the data based on the 3 columns, which are session, class, and course.
From that 2 columns, it's not compulsory to use them where clause for all 2 columns, it can be two columns or one column only. Below is my current query:
SELECT * from tbl_programme where session = '$session' AND class = '$class';
If I run the query with only put data for class and course, it still does not display the specific data that I want. I try to change the use of OR, but still the same. Can anyone help me to solve this?
i should migrate multiple columns of text into one column (in another database). Now i know that it sounds complicated, but i will try my best to explain it.
There is a table in mysql database called "products_desriptions". In that table we have columns like: descriptionDosage, descriptionAction, descriptionIndications and so on. What i want to do is to merge these columns into one column called "productDescription".
Here is an example of what i have done:
SELECT
CONCAT_WS('\ntest', action, Indications, staff, dosage) AS productDescription)
FROM
products_descriptions
WHERE
product_id = 123
So the the columns are being merged successfully.
The problem is that for each column there is a title in the frontpage, which is not being stored into the respective column. For example in the "dosage" column we have text like: "2xday, 14xweek" and so on. And on the frontpage what you can see is something like:
"DOSAGE:
2xday, 14xweek" and so on.
So for each column there is a hard codded title like this one, which i don't know how to get. I mean what i want to do is: to merge columns and respectively for each column i want a title to the respective text.
I am working on php, so maybe it is not possible to be done only by mysql. Maybe i have to do it with php, but has anyone got any idea what exactly should i do?
You can use concat function.
SELECT
CONCAT('\ntest', action, '\nIndictions:', Indications,'\nstaff:', staff,'\ndosage:', dosage) AS productDescription
FROM
products_descriptions
WHERE
product_id = 123
I am trying to replace a column in the result of the select query as denoted in
This reference but unlike the example I have many columns in the table thus I can not specify the name of every column in the select query.
I tried some ways to attain the same but none seems effective.
select
*, (REPLACE(REPLACE(role_id,1,"admin"),2,"moderator") AS role_id
from user;
or
Select *
from user
where role_id = (select REPLACE(role_id,1,"admin") as role_id from user;
Here we assume only two possible values for the role_id however at certain instanced it might have to get data from another table ie a different table that holds different ids and values corresponding to them.
So is there a way to attain the following conditions in a single query:-
to replace values of some fields returned from select query (assuming many columns writing the names of all the columns individually is not feasible)
to get the replacement values from different tables for different columns in single table.
I need to implement the above conditions in one query but the changes shouldn't be in the database only the result of select query needs to be optimized.
Already referred to the following too but could not help.
Link 1
Link 2
Link 3
I am using phpmyadmin as engine and php as the implementation language.
If i have understood your question correctly, it's easier to use CASE/WHEN
SELECT *,
CASE WHEN role_id = 1 THEN "admin" WHEN role_id = 2 THEN "moderator" END AS role_id
FROM user;
But easier still maybe to have an array in PHP,
$roles = array("1" => "admin", "2" => "moderator", .... );
and look it up in the array. that will keep your query short and sweet. The advantage of this approach is that you don't need to change your query every time you add a new role. If you get a large number of roles (say dozens) you might actually want a separate table for that.
I have a trivial question. Im using PHP+MySQL managing a huge DB
I want to search in a entire table a keyword I write in a input.
The problem is that the main table have +100 columns, so I had to write the php query manually
[...]
$sql="select *
from db
where ID LIKE '%".$q."%' or USER_ID LIKE '%".$q."%' or Phone_ID LIKE '%".$q."%' or
Fax_ID LIKE '%".$q."%' or email_ID LIKE '%".$q."%' or [...]
And this is a chaos when I modify a column, or add/remove...
Exist any other way to make this search? If not, I tought about create a separate PHP function, that obtains all column header names, and create an auto-fill function inside.
I tried to look for info with no success
https://stackoverflow.com/search?q=search+entire+table
Unfortunately there isnt any simple way to do this.
One option is to select all columns in table, fetch them as array and iterate over them and build your WHERE clause.
select column_name from information_schema.columns
where table_name = 'TableName'
This will make whole script slower, if you want to go this way i would recommend you to use some caching.
You could get the column info for the 'main table' using info from the information schema. Here are some methods for using MySQL. Here is how to do it using PHP.
You can do a SHOW COLUMNS on the table, then loop over the Field to get all the column names in the table, at least that way you don't have a hand-coded mess to deal with.
This was a bit difficult to explain in the title, but I should be able to here. I have two tables that look like this:
Table 1:
-id
-created
-last_modified
-title
Table 2:
-id
-parent_id
-type
-value
The structure is somewhat akin to the following: an item from table one can have many attributes associated with it. Each attribute is listed in the second table, with a reference back to the original.
The issue I have, is that I want to be able to get a list of records from table 1 to display in a table (using pagination), but also want to be able to retrieve all the attributes from Table 2 associated with each Table 1 record at the same time, so that I might have the following:
(Table 1) ID1 [Title] has attributes x, y, z
(Table 1) ID2 [Title] has attributes x, y, z
(Table 1) ID3 [Title] has attributes x, y, z
and so on. Ideally I would like to be able to associate each attribute with its type as well...currently with a join I receive multiple rows of the same records (with the joined data different each time), and grouping them together removes some of the joined data entirely.
Essentially what I'm after is an array of attributes to be returned for each record from Table 1 (in some sort).
I'm thinking of using MongoDB for this project as I know I can do it simply with that, but I'm trying to do it with MySQL as that is what the existing platform is using.
I hope I've made sense with what I'm asking :) Any help would be appreciated!
Dan
Sounds like more of a display problem. The joined query is the best way to go. You'd then just have a simple loop in your retrieve/display code to check for when you transition from one Table1 record to another and adjust the output as necessary.
You could retrieve all the child records as single fields using MySQL's group_concat() function, but then you just end up with (basically) a monolithic string of concatenated data, and not the individual records the joinedquery/display loop will provide. group_concat also has length-limits on how much data it'll return (1024 bytes by default), which can be easily hit with large data sets.