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
Related
I am using PHP
I have an SQL Table that looks like so:
I am trying to retrieve all rows which contain "9" in the "FAMILY" Column
How would I do so?
Note: The numbers are separated by hyphens "-"
You need to adopt REGEX for that I guess.
SELECT * FROM table_name WHERE family REGEXP '[[:<:]]9[[:>:]]';
Note: May be it's high time you normalized your data. Otherwise you might find it troublesome even for doing the simplest manipulation on that column.
Have a look at this:
Is storing a delimited list in a database column really that bad?
Please try this query:
select * from table_name where concat('-',FAMILY,'-') like '%-9-%';
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 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 :)
I have a PHP interface with a keyword search, working off a DB(MySQL) which has a Keywords field.
The way in which the keywords field is set up is as follows, it is a varchar with all the words formatted as shown below...
the, there, theyre, their, thermal etc...
if i want to just return the exact word 'the' from the search how would this be achieved?
I have tried using 'the%' and '%the' in the PHP and it fails to work by not returning all of the rows where the keyword appears in.
is there a better (more accurate) way to go about this?
Thanks
If you want to select the rows that have exactly the keyword the:
SELECT * FROM table WHERE keyword='the'
If you want to select the rows that have the keyword the anywhere in them:
SELECT * FROM table WHERE keyword LIKE '%the%'
If you want to select the rows that start with the keyword the:
SELECT * FROM table WHERE keyword LIKE 'the%'
If you want to select the rows that end with the keyword the:
SELECT * FROM table WHERE keyword LIKE '%the'
Try this
SELECT * FROM tablename
WHERE fieldname REGEXP '[[:<:]]test[[:>:]]'
[[:<:]] and [[:>:]] are markers for word boundaries.
MySQL Regular Expressions
if you also search for the commas, you can be sure you are getting the whole word.
where keywordField like '%, the, %'
or keywordField like '%, the'
or keywordField like 'the, %'
maybe I didn't understand the question properly... but If you want all the words where 'the' appears, a LIKE '%word%' should work.
If the DB of words is HUGE MySQL may fail to retrieve some of the words, that can be solved in 2 ways...
1- get a DB that support bigger sizes (not many ppl would chose this one tho). For example SQL Server has a 'CONTAINS' function that works better than LIKE '%word%'.
2- use a external search tool that uses inverted index search. I used Sphinx for a project and it works quite good. This is better if you rarely UPDATE the rows of the data you want to search from, which should be the case.
Sphinx for example would generate a file from your MySQL table and use this file to solve the search (it's very fast), this file should be re-indexed everytime you do a insert or update on the table, making it a much better solution if you rarely update or insert new rows.
It looks like you have a one to many relationship going on within a column. It might be better to create a separate table for keywords with a row for each keyword and a foreign key to whatever it is you're searching on.
Doing like '%???%' is generally a bad idea because the DB can't make use of an index so it will scan the whole table. Whether this matters will depend on the size of data you're working with but its worth considering up front. The single best way to help DB performance is in the initial table design. This can be tricky to change later.
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%'