The following statement works fine:
mysql> select concat('/Parent/Child/',date_format(subdate(current_date,1),'%Y/%m/%d'));
+--------------------------------------------------------------------------+
| concat('/Parent/Child/',date_format(subdate(current_date,1),'%Y/%m/%d')) |
+--------------------------------------------------------------------------+
| /Parent/Child/2017/06/14 |
+--------------------------------------------------------------------------+
1 row in set (0.00 sec)
but for some reason I can't do a like comparison with this information. What am I missing here?
I keep getting an empty set which I know is incorrect.
Can someone provide me the correct 'where like ' syntax?
It was actually as easy as concatinating % to before and after initial concat.
Related
I want to convert string to xml column ..
I used below query for that :
Select CONVERT(xml,'<x>' + Replace(A.name,':','</x><x>')+'</x>' ) as xDim from Erecharge;
but it shows error of incorrect sql syntax..
I want to know whats wrong in above query
I also tried this:
Select Cast('<x>' + Replace(A.name,':','</x><x>')+'</x>' as XML) as xDim from Erecharge;
check the manual that corresponds to your MySQL server version for the right syntax to use near 'XML) as xDim from Erecharge'
This means that XML is incorrect in a expression like this:
CAST('foo' AS XML)
As per the docs, the values allowed for CAST type do not include XML.
Additionally, using the + operator on strings is just a convoluted way to render zero:
mysql> SELECT 'a' + 'b';
+-----------+
| 'a' + 'b' |
+-----------+
| 0 |
+-----------+
1 row in set, 2 warnings (0.00 sec)
It's not entirely clear what you're trying to do. MySQL has XML Functions but it doesn't have XML data types. If you just want to produce a string that happens to contain XML code then you need to CONCAT():
mysql> SELECT CONCAT('<date>', CURRENT_TIMESTAMP, '</date>') AS foo;
+----------------------------------+
| foo |
+----------------------------------+
| <date>2018-10-12 11:44:29</date> |
+----------------------------------+
1 row in set (0.00 sec)
... but of course you still need to ensure that angle brackets and similar stuff don't break the XML. CDATA may help. (No idea about XML functions, I'm not familiar with them.)
1- string = a'b"c\d
2- escaped_string = a\'b\"c\\d
3- make an insert query that inserts escaped_string in some table field.
4- make a select query that returns the inserted value.
The returned value is: a'b"c\d
Is there a way to get the select query to return a\'b\"c\\d ?
(I understand that i can escape it again).
You can use the QUOTE() function of mysql:
mysql> select data from x;
+---------+
| data |
+---------+
| a'b"c\d |
+---------+
1 row in set (0.00 sec)
mysql> select quote(data) from x;
+-------------+
| quote(data) |
+-------------+
| 'a\'b"c\\d' |
+-------------+
1 row in set (0.00 sec)
This should exactly do what you are looking for. Note that the " doesn't need to be escaped here, so QUOTE() doesn't escape it, too.
here and in a lot of other websites I have find a lot of posts regarding this question but for some strange reason no one works.
I have a Wordpress database and I need to find all the terms contained in wp_terms that have any special character.
In fact I need to find all that contains anything else of number or letter.
Why this doesn't work? The MySQL query return 0 results.
SELECT * FROM wp_terms WHERE name LIKE '%[^0-9a-zA-Z ]%'
You can use REGEXP to find out this. Also the ^must be outside from [].
SELECT * FROM wp_terms WHERE name REGEXP '[^0-9a-zA-Z ]'
Test
MariaDB [(none)]> SELECT "Hello" REGEXP '[^0-9a-zA-Z ]' as resut;
+-------+
| resut |
+-------+
| 1 |
+-------+
1 row in set (0.00 sec)
MariaDB [(none)]> SELECT "-Hello" REGEXP '[^0-9a-zA-Z ]' as resut;
+-------+
| resut |
+-------+
| 0 |
+-------+
1 row in set (0.00 sec)
It does not work because MySQL supports the ANSI version of LIKE. The form that you are using is an extended form associated with SQL Server.
On the other hand, MySQL supports regular expressions which are much more powerful. The regular expression for what you want is:
WHERE name REGEXP '[^0-9a-zA-Z ]'
Note that regular expressions match the pattern anywhere in the string, so you do not need wildcards at the beginning and the end.
From the command
select char(0x542d01);
I expect
T-1
But MySQL returns
T-:)
From a little of google research I found the result can be modified by specifying the charset in the command, something like
select char(0x542d01 using utf8);
But I wasn't able to find a way to read T-1 from 0x542d01. Would some one give me a hand here, please?
More generally, I think I have a charset issue here.
Function convert can be used to convert data between different charsets.
Reference:
http://dev.mysql.com/doc/refman/5.7/en/charset-convert.html
Here is an example of your data:
mysql> select convert(0x542d01 using utf8);
+------------------------------+
| convert(0x542d01 using utf8) |
+------------------------------+
| T- |
+------------------------------+
1 row in set (0.00 sec)
My table filed's value is "<script type="text/javascript"src="http://localhost:8080/db/widget/10217EN/F"></script>",
I want to analyse this string and fetch the id 10217,how to do use mysql regex?
I know python regex group function can return the id 10217,but i'm not familiar with mysql regex.
Please help me,Thank you very much.
MySQL regular expressions do not support subpattern extraction. You will probably have better luck iterating over all of the rows in your database and storing the results in a new column.
As far as I know, you can't use MySQL's REGEXP for substring retrieval; it is designed for use in WHERE clauses and is limited to returning 0 or 1 to indicate failure or success at a match.
Since your pattern is pretty well defined, you can probably retrieve the id with a query that uses SUBSTR and LOCATE. It will be a bit of a mess since SUBSTR wants the start index and the length of the substring (it would be easier if it took the end index). Perhaps you could use TRIM to chop off the unwanted trailing part.
This query get the Id from the field
SELECT substring_index(SUBSTRING_INDEX(testvar,'/',-3),'EN',1) from testtab;
where as testtab - is table name , testvar - is field name
inner substring get string starts with last 3 / which is
mysql> SELECT SUBSTRING_INDEX(testvar,'/',-3) from testtab;
+----------------------------+
| SUBSTRING_INDEX(testvar,'/',-3) |
+----------------------------+
| 10217EN/F"> |
| 10222EN/F"> |
+----------------------------+
2 rows in set (0.00 sec)
outer substring get
mysql> SELECT substring_index(SUBSTRING_INDEX(testvar,'/',-3),'EN',1) from testtab;
+----------------------------------------------------+
| substring_index(SUBSTRING_INDEX(testvar,'/',-3),'EN',1) |
+----------------------------------------------------+
| 10217 |
| 10222 |
+----------------------------------------------------+
2 rows in set (0.00 sec)