i´m new in SQL and want to solve following case.
I have a table in a MariaDB named inventories. In this table are 2 columns: identifier and data.
I want to select and output a specific part in the column data, if the identifier is a specific one.
For example:
identifier
data
steam:xxxxxxxxxxxxxxx
...some data...,"Serial":"ZF3CJ8L1rrKjwP7nKTzb",...some more data...
The only part, that i want in the output is this: "Serial":"ZF3CJ8L1rrKjwP7nKTzb" but the part behind "Serial":" is a random value.
How can i solve this?
(i put a screenshot in here, table does not work for me in editorscreenshot of table in stackoverflow editor.)
You can try using the SubString function, which only returns a certain amount of character and starts a whatever character you want.
I got it!
SELECT (SUBSTRING(data, LOCATE('"Serial":"', DATA) + 0, 31)) FROM inventories where identifier = 'steam:xxxxxxxxxxxx';
I have a MySQL table setup where one column's values are a string of comma-separated True/False values (1s or 0s). For example, in the column, one field's value may be "0,1,0,0,0,0,1,1,0" and another may be "1,0,0,1,1,1,0,0,0" (note: these are NOT 9 separate columns, but a string in one column). I need to QUERY the MySQL table for elements that are "true"(1) for the "nth element" of that column's value/string.
So, if I was looking for rows, with a specific column, where the 3rd element of the column's value was 1, it would produce a list of results. So, in this case, I would only be searching for "1" in the fth place (12345 = X,X,X...) of the string (X,X,1,X,X,X,X,X,X,X). How can I query this?
This is a crude example of what I am trying to do ...
"SELECT tfcolumn FROM mytable WHERE substr({tfcolumn}, 0, 5)=1"
{tfcolumn} represents the column value
5 represents the 5th position of the string
=1 represents what I need that position to equal to.
Please help. Thanks
You can't. Once you put a serialized data type into a column in SQL (like comma separated lists, or JSON objects) you are preventing yourself from performing any query on the data in those columns. You have to pull the data in a different way and then use a program like python, VB, etc to get the comma separated values you are looking for.
Unless you want to deal with trying to make this mess of a query work...
I would recommend changing your table structure before it's too late. Although it is possible, it is not optimized in a format that a DBMS recognizes. Because of that the DBMS will spend a significant amount of time going through every record to parse the csv values which is something that it was not meant to be doing. Doing the query in SQL will take as much time (if not more time) than just pulling all the records and searching with a tool that can do it properly.
If the column contains values exactly like the ones you posted, then the Nth element is at the 2 * N - 1 position in the comma separated list.
So do this:
SELECT tfcolumn
FROM tablename
WHERE substr(tfcolumn, 2 * 5 - 1, 1) = '1'
Replace 5 with the index that you search for.
See the demo.
Or remove all commas and get the Nth char:
SELECT tfcolumn
FROM tablename
WHERE substr(replace(tfcolumn, ',', ''), 5, 1) = '1'
See the demo.
Try this
if substring_index(substring_index('0,1,0,0,0,0,1,1,0',',',3),',',-1)='1'
The first argument can be your column name. The second argument (',') tells the function that the string is comma-separated. The third argument takes the first 3 elements of the string. So, the output of inner substring_index is '0,1,0'.
The outer substring_index has -1 as the last argment. So, it starts counting in reverse direction & takes only 1 element starting from right.
For example, if the value in a particular row is '2,682,7003,14,185', then the value of substring_index(substring_index('2,682,7003,14,185',',',3),',',-1) is '7003'.
I'm querying an SQL database that I have read only access to (Cannot edit tables/create columns etc)
My table contains a column with JSON strings that have (Actual strings are much larger, this is just an example) the following syntax
{"value":"442","country":"usa"}
I would like to add the values contained in the JSON string from each row together and output it as readable, if this is possible?
The values are in the same point of the JSON, as shown above. The values vary in length also, most are 3/4 characters long.
Try the following (for MySQL v5.7+):
select sum(json_extract(jsonString, '$.value')) from mytable;
An example of this is here.
I am trying to retrieve a list of database records which have specific 'interest codes' inside of the 'custom_fields' table. So for example right now there is 100 records, I need the Name, Email and Interest Code from each of those records.
I've tried with the following statement:
SELECT * FROM `subscribers` WHERE list = '27' AND custom_fields LIKE 'CV'
But with no luck, the response was:
MySQL returned an empty result set (i.e. zero rows). ( Query took 0.0003 sec )
You can see in this screenshot that at-least two rows have 'CV' inside custom_fields. Whilst within the database it's not called 'Interest Code', that's what they are so therefore why I am referencing it in this way.
You need to enclose your "search string" inside some wildcards:
select * from subscribers where list=27 and custom_fields like '%CV%';
The % wildcard means "zero or more chacarcters at this position". The "_" wildcard means "a character in this position". Please read the reference manual on the topic. Also, you may want to read about regular expressions in MySQL for more complex string comparissons.
Is ir possible to sort a column alphabetically but ignoring certain words like e.g 'The'
e.g.
A normal query would return
string 1
string 3
string 4
the string 2
I would like to return
string 1
the string 2
string 3
string 4
Is this possible?
EDIT
Please note I am looking to replace multiple words like The, A, etc... Can this be done?
You can try
SELECT id, text FROM table ORDER BY TRIM(REPLACE(LOWER(text), 'the ', ''))
but note that it will be very slow for large datasets as it has to recompute the new string for every row.
IMO you're better off with a separate column with an index on it.
For multiple stopwords just keep nesting REPLACE calls. :)
This will replace all leading "The " as an example
SELECT *
FROM YourTable
ORDER BY REPLACE(Val,'The ', '')
Yes, it should be possible to use expressions with the ORDER-part:
SELECT * FROM yourTable ORDER BY REPLACE(yourField, "the ", "")
I have a music listing that is well over 75,000 records and I had encountered a similar situation. I wrote a PHP script that checked for all string that began with 'A ', 'An ' or 'The ' and truncated that part off the string. I also converted all uppercase letters to lowercase and stored that string in a new column. After setting an index on that column, I was done.
Obviously you display the initial column but sort by the newly-created indexed column. I get results in a second or so now.