I am having a table with a column that has few ids that were put into database with multi select. Column for example contains: 1,4,5,7,9. Is it possible to check if this column contains for example number 5 or not in it through MySQL query ?.
I need to select all the people that have number 5 or some other listed in that field and print them through php.
http://dev.mysql.com/doc/refman/5.6/en/string-functions.html#function_find-in-set
SELECT ...
WHERE FIND_IN_SET(5, list_column)
But understand that this search is bound to be very slow. It cannot use an index, and it will cause a full table-scan (reading every row in the table). As the table grows, the query will become unusably slow.
Please read my answer to Is storing a delimited list in a database column really that bad?
You can use #MikeChristensen's answer to be more standard. Another trick with standard SQL is this:
select * from TableName
where ',' || ids || ',' LIKE '%,5,%'
(in standard SQL, || is the string concatenation operator, but in MySQL, you have to SET SQL_MODE=PIPES_AS_CONCAT or SET SQL_MODE=ANSI to get that behavior.)
Another MySQL-specific solution is to use a special word-boundary regular expression, which will match either the comma punctuation or beginning/end of string:
select * from TableName
where ids RLIKE '[[:<:]]5[[:>:]]'
None of these solutions scale well; they all cause table-scans. Sorry I understand you cannot change the database design, but if your project next requires to make the query faster, you can tell them it's not possible without redesigning the table.
Perhaps:
select * from TableName
where ids = '5' -- only 5
or ids like '5,%' -- begins with 5
or ids like '%,5' -- ends with 5
or ids like '%,5,%' -- 5 in the middle somewhere
It probably won't be very fast on large amounts of data. I'd suggest normalizing these multi-selection values into a new table, where each selection is a single row with a link to TableName.
select * from your_table where concat(',',target_column,',') like '%,5,%'
you can write the sql query like this, for example you are looking for the number 5
select * from your_table_name where ids='5'
if you want to check the result with php just tell me i will write it for you :)
Related
I would like to write an sql statement for search. Here is sample database structure.
For eg, I want to display all records with topic '13'. How can i write sql query for searching 13 from the above structure? Any suggestions?
Can i able to use WHERE Topic LIKE '%13%'? Anything wrong with this?
Try this one:
SELECT * FROM `TABLE_NAME` WHERE `Topic` LIKE "%13%";
It's better and faster to save it in a third table of many-to-many relationship.
If you want to save as per your example (single table), try to save data as eg ",10,13,15,"
always have coma before and after, thus the following sql will exclude 213 and 132 etc
select * from table_name where Topic like '%,13,%'
select * from table where find_in_set("13",topic);
or if topic is not used as a set, you could do ...
select * from table where concat(",",topic) like "%,13,%";
The 2nd isn't real elegant but I've had to do that a couple times.
Because the data isn't really normalized, I used concat to add a comma to the topic field so I could make sure the "like" comparison would pass with a comma before and after the value. I suppose we would also have to remove any unwanted spaces as well for this example, so ultimately it would end up like:
select * from TABLE where concat(",",replace(topic," ","")) like "%,13,%";
Ultimately, we have to know what to expect in the topic column to come up with a query that would always work. In the past, I've had situations where I would add values to a string field (i.e. topic) with a delimiter before and after each value like:
(1)(2)(3)(14)(15)(255)(283)
If you did something like this for the topic field, the query is simple ...
select * from table where topic like "%(13)%";
How to query comma delimited field of table to see if number is within the field
I want to select rows from a table if a column contains a certain number e.g 981. The data in these columns is either 0, null or in the format below:
1007,1035,1189,908,977,974,979,973,982,981,1007
I made a like as in above link. I used IN ('7','3','12','1','10','13','2') & it gets only 22K of rows from Table. For the same query If i use REGEXP '7|3|12|1|10|13|2' it returs nearly 119K rows from same Table. but REGEXP makes slow the query. is there any method to make my query faster?
Your regexp is confusing values. So, 7 matches 17 and 77. The in does what you want.
First, I don't recommend storing values in a comma-delimited list. If you really have to (like someone who didn't know better designed the database), then use find_in_set():
where find_in_set(7, list) > 0 or
find_in_set(3, list) > 0 or
. . .
Alternatively, put delimiters in the regexp. I think it would look like:
where concat(',', list, ',') regexp '(,7,)|(,3,)|(,12,)|(,1,)|(,10,)|(,13,)|(,2,)'
I have 100K datas in my mysql database, I want to search a query in it. I removed stop-words and splitted it into an array of keywords and stored in a variable ie $key[0],$key[1],$key[2].I am using the following query
SELECT *
FROM `table`
WHERE (`column` LIKE '%$key1%'
OR `column` LIKE '%$key2%'
OR `column` LIKE '%$key3%');
is any other faster ways to do the same.
The only way to speed up queries like this is to use full-text searching. LIKE '%string%' can't be optimized with normal indexes, because they use B-trees that depend on matching the prefix of the string being searched for. Since your pattern begins with a wildcard, the index doesn't help.
Another solution is to normalize your database. Don't put the keywords all in one column, put them in another table, with a foreign key to this table and a row for each FK+keyword. Then you can use a join to match the keywords.
Also, you're using the wrong type of quotes around your column names. They should be backticks, not single quotes.
you can do something like this
SELECT *
FROM table
WHERE colomn REGEXP '$key1|$key2|$key3'
etc etc so instead of creating your array as a comma separated list of key words do it as a pipe separated list and then just push the string into your regex too this is simply an example
Don't SELECT *, only select what you need.
If you want to do complete-text searches, lose the % and add an index
You misspelled column
I have a database and some of the columns contain things like CA, GB etc, although some contain multiple country codes like
US+GB+CA+AU
I'm just wondering what kind of query I would do that would return that row when I'm searching for just CA or just GB, and no necessarily the whole package US+GB+CA+AU
Encase that's a little confusing, basically I just need to return that row based on a search for just CA or just GB etc.
Thanks
Use FIND_IN_SET(), but you'll first need to replace + with , since it expects a comma-separated string. Even without the
REPLACE(), this is will not make use of any index on the countrycodes column.
SELECT * FROM tbl
WHERE FIND_IN_SET('AU', REPLACE(countrycodes, '+', ',')) > 0
The proper long term solution, however, is to change your database structure to normalize these country codes into a table that contains only two columns - a country code, and the id of the associated row from the table you're attempting to query now. You can then index the column appropriately to improve performance (possibly drastically improve it).
I would recommend to normalise it like liquorvicar said.
but using SELECT ... WHERE countrycode LIKE '%GB%' would work.
http://w3schools.com/sql/sql_like.asp
It's not a good solution, but you can use LIKE for your query:
SELECT * FROM `table` WHERE `field` LIKE '%+CA+%' OR `field` LIKE 'CA+%' OR `field` LIKE '%+CA' OR `field` = 'CA'
Last two checks for firs and last values.
I want to filter result of my SQL query. I want to select everything that has some specific text in some column.
Example:
SELECT * FROM categories WHERE (name
has 'abc' values in it's value ex.
MyabcCategory)
Also maybe it is not very good idea to do that in query, maybe it is better to get all and then filter array instead? But I don't know how to do that aether.
Use LIKE with % wildcard:
SELECT * FROM categories WHERE name LIKE '%abc%'
This will give you all the records that have abc somewhere in them.
You can learn more about it here :)
You want to use the LIKE operator, with % to match any character before and after your specific word :
select *
from categories
where name like '%abc%';
But note that doing so, MySQL will scan each line of the table, every time the query is executed... which might not be great if you have a lot of data.
If you're searching for some kind of text, you might either want to :
Use a FULLTEXT index, if you're working with MyISAM tables.
Or, use a solution that's separated from MySQL, with a specific indexing/search engine, such as Solr.
SELECT * FROM categories WHERE name LIKE '%abc%'