I have a databse of english words and i want to use regexp to search in this database
i used this query :
SELECT * FROM `english` WHERE CHAR_LENGTH(words)=4 AND `words` REGEXP '^[oofd]+$'
it is working and its selecting the words like food,foo,of,do
but it is also selecting the words like fooo with 3 o's but in my regexp there is just 2 o's
what is the right regular expression to select words with no repeating characters
if there is two character for example oo it will select just words with two o or 1 or zero ,not three or more
I looked in the internet i came with this:
^(?:([oofd])(?!.*\1))
but it gives me an error:
#1139 - Got error 'repetition-operator operand invalid' from regexp
Check for the presence of two vowels in sequence and the absence of three or more vowels in sequence:
SELECT *
FROM english
WHERE
words REGEXP '^.*[aeiou]{2}.*$' AND
words NOT REGEXP '^.*[aeiou]{3}.*$'
If you only want to look for certain repeated vowels, you should be able to adapt this answer fairly easily.
Related
I want to searching for the term 'ed' at the start or end of a word, the following SQL statement only matches a exact word match.
SELECT * FROM ul_product
where productname REGEXP '\\bed\\b'
If I do the following it gets results where ed is at the start or end of a word
SELECT * FROM ul_product
where productname REGEXP '(\\bed)|(ed\\b)'
Is this how it's supposed to work?
The description of word boundary and examples online led me to believe statement 1 would produce the results of statement 2.
I can use the statements I've created as is for my 'exact' and 'partial' matching, but is this right?
Regex '\\bed\\b' searches for 'ed' surrounded by word boundaries - in other words it searches for word 'ed'.
On the other end, regex: '(\\bed)|(ed\\b)' searches for either '\\bed' or 'ed\\b' (the pipe character stands for "or" in regexes). So it matches on 'ed' at the beginning of a word or at the end of a word - which seems to be what you want.
Note that the parentheses are not necessary here. You could just write this as:
where productname REGEXP '\\bed|ed\\b'
Hello I have made a dummy table that I am practicing with and I am trying to get the lasts name first letter for example. Aba Kadabra and Alfa Kadabra the last letter of their last name is 'K' so when I was testing some queries such as...
select * from employees
where full_name like 'K%'
select * from employees
where full_name like 'K%'
Neither of these worked. Can anyone tell me the best way to accomplish this?
Because % works that way. See here
So, 'K%' just brings all full_name that start with K.
and '%K' brings all full_name that end with K.
What you need is '% K%', test it please.
MySQL LIKE operator checks whether a specific character string matches
a specified pattern.
The LIKE operator does a pattern matching comparison. The operand to
the right of the LIKE operator contains the pattern and the left hand
operand contains the string to match against the pattern. A percent
symbol ("%") in the LIKE pattern matches any sequence of zero or more
characters in the string. An underscore ("_") in the LIKE pattern
matches any single character in the string. Any other character
matches itself or its lower/upper case equivalent (i.e.
case-insensitive matching). (A bug: SQLite only understands
upper/lower case for ASCII characters by default. The LIKE operator is
case sensitive by default for unicode characters that are beyond the
ASCII range. For example, the expression 'a' LIKE 'A' is TRUE but 'æ'
LIKE 'Æ' is FALSE.)
You can use below query:
select * from table where full_name like '% K%'
This question already has answers here:
Search string by exact word in Mysql
(9 answers)
Closed 5 years ago.
I have a MySQL table with a list of sentences such as:
id | Sentence
---+---------------------------------------------------------------
1 | Come On Boys, You Can do it my boy.
2 | Everything is possible, impossible itself says I am possible.
3 | Boys I know possible solutions are good!
4 | Possible solutions are all failed its also possible
I have to search on Sentence column exact word like possible.
There are some condition :
Searching word can't be prefix or suffix of any word.
Searching word possible , impossible is incorrect.
Punctuation mark can be before or after the word.Ex: !boy or boy,
No case sensitive means for possible Possible is correct.
I try a query but it is not working
mysql_query("SELECT * FROM products WHERE Sentence LIKE '%".$search."%'");
Possible punctuation mark are ,.!?;-
I need a working solution. Thanks in advance !
You could use REGEXP:
SELECT *
FROM products
WHERE Sentence REGEXP '[[:<:]]possible[[:>:]]'
-- ^^^ ^^^ word boundaries
This would correspond to matching possible surrounded by a word boundary. Note in the demo that punctuation counts as a word boundary.
Also note that MySQL's REGEXP is case insensitive, so the above should match possible or Possible.
Demo here:
Rextester
Use REGEXP:
SELECT *
FROM products
WHERE Sentence REGEXP '[^\\d\\w]possible[^\\d\\w]'
This takes every word possible surrounded by any word or number.
Be carefull with case sensitivity.
CREATE TEMPORARY TABLE tmp (id INTEGER PRIMARY KEY AUTO_INCREMENT, sentence VARCHAR(200));
INSERT INTO tmp (sentence) VALUES ('Come On Boys, You Can do it my boy.');
INSERT INTO tmp (sentence) VALUES ('Everything is possible, impossible itself says I am possible.');
INSERT INTO tmp (sentence) VALUES ('Boys I know possible solutions are good!');
INSERT INTO tmp (sentence) VALUES ('Possible solutions are all failed its also possible');
SELECT * FROM tmp WHERE sentence REGEXP '[[:<:]]impossible[[:>:]]';
This is duplicate: Search for "whole word match" in MySQL
my table has a column with comma-separated (and eventually a space, too) numbers; those numbers can have from five to twelve digits.
9645811, 9646011,9645911, 9646111
or
41031, 41027, 559645811, 5501006009
I need to select the rows with that column containing a number STARTING with given digits. In the above examples, only the first has to be selected. What I've tried so far:
SELECT myfield FROM mytable
WHERE myfield REGEXP ('(^|[,\s]+)(96458[\d]*)([,\s]*|$)');
However the query returns no results. I'd like to select only the first row, where there is a number STARTING with 96458.
Any help would be appreciated :)
You need to use a starting word boundary [[:<:]]:
SELECT myfield FROM mytable WHERE myfield REGEXP ('[[:<:]]96458');
See the MySQL regex syntax for more details.
[[:<:]], [[:>:]]
These markers stand for word boundaries. They match the beginning and end of words, respectively.
See this SQL fiddle.
I have a table with 1/2 million phrases and I am doing word matching using this query:
SELECT * FROM `searchIndex` WHERE `indexData` RLIKE '[[:<:]]Hirt'
The indexData field has a FULLTEXT index and is datatype longtext.
I want to match on items like
"Alois M. Hirt"
"Show Biz - Al Hirt, in a new role, ..."
"Al Hirt's Sinatraville open 9 p..."
"Hirt will be playing..."
and not on "shirt" or "thirteen" or "thirty" etc.
The query is succeeding but it frequently takes 3 seconds to return and I wondered if there was a better, more efficient way of doing this word boundary match?
If I were to add another index to indexData what would be the correct keylength to use?
TIA
No need to have a FULLTEXT index. MySQL has special markers for word boundaries. From the MySQL doc:
[[:<:]], [[:>:]]
These markers stand for word boundaries. They match the beginning and end of words, respectively. A word is a sequence of word characters that is not preceded by or followed by word characters. A word character is an alphanumeric character in the alnum class or an underscore (_).
mysql> SELECT 'a word a' REGEXP '[[:<:]]word[[:>:]]'; -> 1
mysql> SELECT 'a xword a' REGEXP '[[:<:]]word[[:>:]]'; -> 0
setsuna's answer worked very well:
SELECT * FROM searchIndex WHERE MATCH (indexData) AGAINST ('Hirt*' IN BOOLEAN MODE);