is it possible to compare a string against a list using "like" and wildcards, so sth like
select column
from table
where column like('%foo%', '%bar%')
The example does not work in any database format I know. How can I do this without using a verbose solution like
select column
from table
where column like'%foo%' or column like '%bar%'
I am interested in a platform-independent solution but mainly Sybase ASE.
Thanks very much!
If you are using MySQL/PostgreSQL you could use regexp, that is one way.
SELECT column FROM table WHERE (column REGEXP '^ALA[0-9]')
http://dev.mysql.com/doc/refman/5.0/en/regexp.html#operator_regexp
http://www.oreillynet.com/pub/a/databases/2006/02/02/postgresq_regexes.html
Second solution would be, mentioned by you creating many likes, joined by or.
Related
i have an array of strings and a column which may contain one or more of those strings(seperated by space) i want to get all rows where this column contains one of the strings. Since the values all have 3 letters and therefore can't contain each other, i know i could just write
SELECT * FROM table WHERE
column LIKE '%val1%' OR
column LIKE '%val2%' OR
column LIKE '%val3%' OR
column LIKE '%val4%'
But i'm wondering if there isn't an easier statement, like column IN ('val1', 'val2', 'val3', 'val4') (This one seems only to work when the entry is equal to one of the values, but not if it just contains them)
Try reading this Is there a combination of "LIKE" and "IN" in SQL? and Combining "LIKE" and "IN" for SQL Server , this will solve you question.
Something like this from the first link.
SQL Server:
WHERE CONTAINS(t.something, '"bla*" OR "foo*" OR "batz*"')
Ist oracle you could use regular expressions
select *
from table
where regexp_like (column,'val(1|2|3|4)')
My overall goal is to create new tables by selecting columns in existing tables with certain patterns/tags in their column names. This is in SQL Server.
For example, I have a common need to get all contact information out of a company table, and into its own contact table.
I haven't been able to find a programmatic approach in SQL to express excluding columns from a SELECT statement based on string.
When looking to options like the COL_NAME function, those require an ID arg, which kills that option for me.
Wishing there was something built in that could work like the following:
SELECT *
FROM TABLE
WHERE COL_NAME() LIKE 'FLAG%'
Any ideas? Open to anything! Thanks!!
One trick could be to firstly using the following code to get the column names you desire:
select * from information_schema.columns
where table_name='tbl' and column_name like 'FLAG%'
Then concatenate them into a comma-delimited string and finally create a dynamic sql query using the created string as the column names.
I would like to ask if it is possible to do this:
For example the search string is '009' -> (consider the digits as string)
is it possible to have a query that will return any occurrences of this on the database not considering the order.
for this example it will return
'009'
'090'
'900'
given these exists on the database. thanks!!!!
Use the Like operator.
For Example :-
SELECT Marks FROM Report WHERE Marks LIKE '%009%' OR '%090%' OR '%900%'
Split the string into individual characters, select all rows containing the first character and put them in a temporary table, then select all rows from the temporary table that contain the second character and put these in a temporary table, then select all rows from that temporary table that contain the third character.
Of course, there are probably many ways to optimize this, but I see no reason why it would not be possible to make a query like that work.
It can not be achieved in a straight forward way as there is no sort() function for a particular value like there is lower(), upper() functions.
But there is some workarounds like -
Suppose you are running query for COL A, maintain another column SORTED_A where from application level you keep the sorted value of COL A
Then when you execute query - sort the searchToken and run select query with matching sorted searchToken with the SORTED_A column
I have the following SQL query:
SELECT Phrases.*
FROM Phrases
WHERE (((Phrases.phrase) Like "*ing aids*")
AND ((Phrases.phrase) Not Like "*getting*")
AND ((Phrases.phrase) Not Like "*contracting*"))
AND ((Phrases.phrase) Not Like "*preventing*"); //(etc.)
Now, if I were using RegEx, I might bunch all the Nots into one big (getting|contracting|preventing), but I'm not sure how to do this in SQL.
Is there a way to render this query more legibly/elegantly?
Just by removing redundant stuff and using a consistent naming convention your SQL looks way cooler:
SELECT *
FROM phrases
WHERE phrase LIKE '%ing aids%'
AND phrase NOT LIKE '%getting%'
AND phrase NOT LIKE '%contracting%'
AND phrase NOT LIKE '%preventing%'
You talk about regular expressions. Some DBMS do have it: MySQL, Oracle... However, the choice of either syntax should take into account the execution plan of the query: "how quick it is" rather than "how nice it looks".
With MySQL, you're able to use regular expression where-clause parameters:
SELECT something FROM table WHERE column REGEXP 'regexp'
So if that's what you're using, you could write a regular expression string that is possibly a bit more compact that your 4 like criteria. It may not be as easy to see what the query is doing for other people, however.
It looks like SQL Server offers a similar feature.
Sinec it sounds like you're building this as you go to mine your data, here's something that you could consider:
CREATE TABLE Includes (phrase VARCHAR(50) NOT NULL)
CREATE TABLE Excludes (phrase VARCHAR(50) NOT NULL)
INSERT INTO Includes VALUES ('%ing aids%')
INSERT INTO Excludes VALUES ('%getting%')
INSERT INTO Excludes VALUES ('%contracting%')
INSERT INTO Excludes VALUES ('%preventing%')
SELECT
*
FROM
Phrases P
WHERE
EXISTS (SELECT * FROM Includes I WHERE P.phrase LIKE I.phrase) AND
NOT EXISTS (SELECT * FROM Excludes E WHERE P.phrase LIKE E.phrase)
You are then always just running the same query and you can simply change what's in the Includes and Excludes tables to refine your searches.
Depending on what SQL server you are using, it may support REGEX itself. For example, google searches show that SQL Server, Oracle, and mysql all support regex.
You could push all your negative criteria into a short circuiting CASE expression (works Sql Server, not sure about MSAccess).
SELECT *
FROM phrases
WHERE phrase LIKE '%ing aids%'
AND CASE
WHEN phrase LIKE '%getting%' THEN 2
WHEN phrase LIKE '%contracting%' THEN 2
WHEN phrase LIKE '%preventing%' THEN 2
ELSE 1
END = 1
On the "more efficient" side, you need to find some criteria that allows you to avoid reading the entire Phrases column. Double sided wildcard criteria is bad. Right sided wildcard criteria is good.
I am new to SQL programming.
I have a table job where the fields are id, position, category, location, salary range, description, refno.
I want to implement a keyword search from the front end. The keyword can reside in any of the fields of the above table.
This is the query I have tried but it consist of so many duplicate rows:
SELECT
a.*,
b.catname
FROM
job a,
category b
WHERE
a.catid = b.catid AND
a.jobsalrange = '15001-20000' AND
a.jobloc = 'Berkshire' AND
a.jobpos LIKE '%sales%' OR
a.jobloc LIKE '%sales%' OR
a.jobsal LIKE '%sales%' OR
a.jobref LIKE '%sales%' OR
a.jobemail LIKE '%sales%' OR
a.jobsalrange LIKE '%sales%' OR
b.catname LIKE '%sales%'
For a single keyword on VARCHAR fields you can use LIKE:
SELECT id, category, location
FROM table
WHERE
(
category LIKE '%keyword%'
OR location LIKE '%keyword%'
)
For a description you're usually better adding a full text index and doing a Full-Text Search (MyISAM only):
SELECT id, description
FROM table
WHERE MATCH (description) AGAINST('keyword1 keyword2')
SELECT
*
FROM
yourtable
WHERE
id LIKE '%keyword%'
OR position LIKE '%keyword%'
OR category LIKE '%keyword%'
OR location LIKE '%keyword%'
OR description LIKE '%keyword%'
OR refno LIKE '%keyword%';
Ideally, have a keyword table containing the fields:
Keyword
Id
Count (possibly)
with an index on Keyword. Create an insert/update/delete trigger on the other table so that, when a row is changed, every keyword is extracted and put into (or replaced in) this table.
You'll also need a table of words to not count as keywords (if, and, so, but, ...).
In this way, you'll get the best speed for queries wanting to look for the keywords and you can implement (relatively easily) more complex queries such as "contains Java and RCA1802".
"LIKE" queries will work but they won't scale as well.
Personally, I wouldn't use the LIKE string comparison on the ID field or any other numeric field. It doesn't make sense for a search for ID# "216" to return 16216, 21651, 3216087, 5321668..., and so on and so forth; likewise with salary.
Also, if you want to use prepared statements to prevent SQL injections, you would use a query string like:
SELECT * FROM job WHERE `position` LIKE CONCAT('%', ? ,'%') OR ...
I will explain the method i usally prefer:
First of all you need to take into consideration that for this method you will sacrifice memory with the aim of gaining computation speed.
Second you need to have a the right to edit the table structure.
1) Add a field (i usually call it "digest") where you store all the data from the table.
The field will look like:
"n-n1-n2-n3-n4-n5-n6-n7-n8-n9" etc.. where n is a single word
I achieve this using a regular expression thar replaces " " with "-".
This field is the result of all the table data "digested" in one sigle string.
2) Use the LIKE statement %keyword% on the digest field:
SELECT * FROM table WHERE digest LIKE %keyword%
you can even build a qUery with a little loop so you can search for multiple keywords at the same time looking like:
SELECT * FROM table WHERE
digest LIKE %keyword1% AND
digest LIKE %keyword2% AND
digest LIKE %keyword3% ...
You can find another simpler option in a thread here: Match Against.. with a more detail help in 11.9.2. Boolean Full-Text Searches
This is just in case someone need a more compact option. This will require to create an Index FULLTEXT in the table, which can be accomplish easily.
Information on how to create Indexes (MySQL): MySQL FULLTEXT Indexing and Searching
In the FULLTEXT Index you can have more than one column listed, the result would be an SQL Statement with an index named search:
SELECT *,MATCH (`column`) AGAINST('+keyword1* +keyword2* +keyword3*') as relevance FROM `documents`USE INDEX(search) WHERE MATCH (`column`) AGAINST('+keyword1* +keyword2* +keyword3*' IN BOOLEAN MODE) ORDER BY relevance;
I tried with multiple columns, with no luck. Even though multiple columns are allowed in indexes, you still need an index for each column to use with Match/Against Statement.
Depending in your criterias you can use either options.
I know this is a bit late but what I did to our application is this. Hope this will help someone tho. But it works for me:
SELECT * FROM `landmarks` WHERE `landmark_name` OR `landmark_description` OR `landmark_address` LIKE '%keyword'
OR `landmark_name` OR `landmark_description` OR `landmark_address` LIKE 'keyword%'
OR `landmark_name` OR `landmark_description` OR `landmark_address` LIKE '%keyword%'