id text_1 text_2
1 おはよう おはよ
2 こんにちは ちわー
3 大丈夫 さよなら
4 でんわしたい でんわしよう
I have DB same above.
I want to search with input: おはよう大丈夫？
Expect result will match: id = 1 and id = 3.
Please help me how to query search in Mysql? Thanks you.
The following SQL query will fetch your 2 ids for exact string matching
select id from TABLENAME where text_1 in ('おはよう','大丈夫');
You can also use like operator with % to fetch approximately strings id.
You might face encoding issue (文字化け）depending on your DB settings, so you might have to convert SJIS <-> UTF-8
https://dev.mysql.com/doc/refman/5.7/en/faqs-cjk.html#faq-cjk-what-cjk-avail
Last but not least, if you want to use the full string as a comparison criteria to select the rows, then you can reuse the following code:
how to compute similarity between two strings in MYSQL
select id from TABLENAME where text_1 REGEXP "おはよう大丈夫"
I am trying to write a Query to find if a string contains part of the value in Column (Not to confuse with the query to find if a column contains part of a string).
Say for example I have a column in a table with values
ABC,XYZ
If I give search string
ABCDEFG
then I want the row with ABC to be displayed.
If my search string is XYZDSDS then the row with value XYZ should be displayed
The answer would be "use LIKE".
See the documentation: https://dev.mysql.com/doc/refman/5.0/en/string-comparison-functions.html
You can do WHERE 'string' LIKE CONCAT(column , '%')
Thus the query becomes:
select * from t1 where 'ABCDEFG' LIKE CONCAT(column1,'%');
If you need to match anywhere in the string:
select * from t1 where 'ABCDEFG' LIKE CONCAT('%',column1,'%');
Here you can see it working in a fiddle:
http://sqlfiddle.com/#!9/d1596/4
Select * from table where #param like '%' + col + '%'
First, you appear to be storing lists of things in a column. This is the wrong approach to storing values in the database. You should have a junction table, with one row per entity and value -- that is, a separate row for ABC and XYZ in your example. SQL has a great data structure for storing lists. It is called a "table", not a "string".
If you are stuck with such a format and using MySQL, there is a function that can help:
where find_in_set('ABC', col)
MySQL treats a comma delimited string as a "set" and offers this function. However, this function cannot use indexes, so it is not particularly efficient. Did I mention that you should use a junction table instead?
I am looking to build a query which can find values in string. For eg my column demo has following 2 rows:
1,2,121,43
343,21
My current query is:
select * from table where demo like '%21%'
However, this returns both the rows. I want to look for the exact match in the string.
Use FIND_IN_SET()
select * from table
where find_in_set(21, demo) > 0
But actually you should really change your table structure. Never store multiple values in one column!
I have this table under user_name='high'
function_description :
akram is in a date
test
akram is studying
test4
kheith is male
test3
I want a query that returns results of field that have at least an 'akram'
SELECT *
FROM functions
WHERE 'isEnabled'=1
AND 'isPrivate'=1
AND user_name='high'
AND function_description LIKE '%akram%'
and this returns absolutely nothing!
Why?
You are listing the column names as if they are strings. This is why it returns nothing.
Try this:
SELECT *
FROM functions
WHERE user_name='high'
AND function_description LIKE '%akram%'
edit: After trying to re-read your question... are isEnabled and isPrivate columns in this table?
edit2: updated.. remove those unknown columns.
You are comparing strings 'isEnabled' with integer 1, which likely leads to the integer being converted to a string, and the comparison then fails. (The alternative is that the string is converted to an integer 0 and the comparison still fails.)
In MySQL, you use back-quotes, not single quotes, to quote column and table names:
SELECT *
FROM `functions`
WHERE `isEnabled` = 1
AND `isPrivate` = 1
AND `user_name` = 'high'
AND `function_description` LIKE '%akram%'
In standard SQL, you use double quotes to create a 'delimited identifier'; in Microsoft SQL Server, you use square brackets around the names.
Please show the schema more carefully (column names, sample values, types if need be) next time.
What's the difference between
SELECT foo FROM bar WHERE foobar='$foo'
AND
SELECT foo FROM bar WHERE foobar LIKE'$foo'
= in SQL does exact matching.
LIKE does wildcard matching, using '%' as the multi-character match symbol and '_' as the single-character match symbol. '\' is the default escape character.
foobar = '$foo' and foobar LIKE '$foo' will behave the same, because neither string contains a wildcard.
foobar LIKE '%foo' will match anything ending in 'foo'.
LIKE also has an ESCAPE clause so you can set an escape character. This will let you match literal '%' or '_' within the string. You can also do NOT LIKE.
The MySQL site has documentation on the LIKE operator. The syntax is
expression [NOT] LIKE pattern [ESCAPE 'escape']
LIKE can do wildcard matching:
SELECT foo FROM bar WHERE foobar LIKE "Foo%"
If you don't need pattern matching, then use = instead of LIKE. It's faster and more secure. (You are using parameterized queries, right?)
Please bear in mind as well that MySQL will do castings dependent upon the situation: LIKE will perform string cast, whereas = will perform int cast. Considering the situation of:
(int) (vchar2)
id field1 field2
1 1 1
2 1 1,2
SELECT *
FROM test AS a
LEFT JOIN test AS b ON a.field1 LIKE b.field2
will produce
id field1 field2 id field1 field2
1 1 1 1 1 1
2 1 1,2 1 1 1
whereas
SELECT *
FROM test AS a
LEFT JOIN test AS b ON a.field1 = b.field2
will produce
id field1 field2 id field1 field2
1 1 1 1 1 1
1 1 1 2 1 1,2
2 1 1,2 1 1 1
2 1 1,2 2 1 1,2
According to the MYSQL Reference page, trailing spaces are significant in LIKE but not =, and you can use wildcards, % for any characters, and _ for exactly one character.
I think in term of speed = is faster than LIKE. As stated, = does an exact match and LIKE can use a wildcard if needed.
I always use = sign whenever I know the values of something. For example
select * from state where state='PA'
Then for likes I use things like:
select * from person where first_name like 'blah%' and last_name like 'blah%'
If you use Oracle Developers Tool, you can test it with Explain to determine the impact on the database.
The end result will be the same, but the query engine uses different logic to get to the answer. Generally, LIKE queries burn more cycles than "=" queries. But when no wildcard character is supplied, I'm not certain how the optimizer may treat that.
With the example in your question there is no difference.
But, like Jesse said you can do wildcard matching
SELECT foo FROM bar WHERE foobar LIKE "Foo%"
SELECT foo FROM bar WHERE foobar NOT LIKE "%Foo%"
More info:
http://dev.mysql.com/doc/refman/5.0/en/string-comparison-functions.html
A little bit og google doesn't hurt...
A WHERE clause with equal sign (=) works fine if we want to do an exact match. But there may be a requirement where we want to filter out all the results where 'foobar' should contain "foo". This can be handled using SQL LIKE clause alongwith WHERE clause.
If SQL LIKE clause is used along with % characters then it will work like a wildcard.
SELECT foo FROM bar WHERE foobar LIKE'$foo%'
Without a % character LIKE clause is very similar to equal sign alongwith WHERE clause.
In your example, they are semantically equal and should return the same output.
However, LIKE will give you the ability of pattern matching with wildcards.
You should also note that = might give you a performance boost on some systems, so if you are for instance, searching for an exakt number, = would be the prefered method.
Looks very much like taken out from a PHP script. The intention was to pattern-match the contents of variable $foo against the foo database field, but I bet it was supposed to be written in double quotes, so the contents of $foo would be fed into the query.
As you put it, there is NO difference.
It could potentially be slower but I bet MySQL realises there are no wildcard characters in the search string, so it will not do LIKE patter-matching after all, so really, no difference.
In my case I find Like being faster than =
Like fetched a number of rows in 0.203 secs the first time then 0.140 secs
= returns fetched the same rows in 0.156 secs constantly
Take your choice
I found an important difference between LIKE and equal sign = !
Example: I have a table with a field "ID" (type: int(20) ) and a record that contains the value "123456789"
If I do:
SELECT ID FROM example WHERE ID = '123456789-100'
Record with ID = '123456789' is found (is an incorrect result)
If I do:
SELECT ID FROM example WHERE ID LIKE '123456789-100'
No record is found (this is correct)
So, at least for INTEGER-fields it seems an important difference...