I'd like to extract texts based on some key words from Hive database.
It works if my script looks like,
SELECT text
FROM table
WHERE text RLIKE '.?(aaa|bbb|ccc).?';
But in order to make the script more readable, I'd like to set the key words as a variable in hive. But the script fails if it looks like,
SET hivevar:KeyWords='.?(aaa|bbb|ccc).?';
SELECT text
FROM table
WHERE text RLIKE ${hivevar:KeyWords};
Any idea? Thanks.
Fu
I use hivevar for variable substitution:
set myVar='.?(aaa|bbb|ccc).?';
select * from <your table> where <your column> RLIKE ${myVar};
edit:fixing brain fart...
Related
I looked around some and didn't find what I was after so here goes.
SELECT * FROM trees WHERE trees.`title` LIKE '%elm%'
This works fine, but not if the tree is named Elm or ELM etc...
How do I make SQL case insensitive for this wild-card search?
I'm using MySQL 5 and Apache.
I've always solved this using lower:
SELECT * FROM trees WHERE LOWER( trees.title ) LIKE '%elm%'
SELECT *
FROM trees
WHERE trees.`title` COLLATE UTF8_GENERAL_CI LIKE '%elm%'
Actually, if you add COLLATE UTF8_GENERAL_CI to your column's definition, you can just omit all these tricks: it will work automatically.
ALTER TABLE trees
MODIFY COLUMN title VARCHAR(…) CHARACTER
SET UTF8 COLLATE UTF8_GENERAL_CI.
This will also rebuild any indexes on this column so that they could be used for the queries without leading '%'
The case sensitivity is defined in the columns / tables / database collation settings. You can do the query under a specific collation in the following way:
SELECT *
FROM trees
WHERE trees.`title` LIKE '%elm%' COLLATE utf8_general_ci
for instance.
(Replace utf8_general_ci with whatever collation you find useful). The _ci stands for case insensitive.
This is the example of a simple LIKE query:
SELECT * FROM <table> WHERE <key> LIKE '%<searchpattern>%'
Now, case-insensitive using LOWER() func:
SELECT * FROM <table> WHERE LOWER(<key>) LIKE LOWER('%<searchpattern>%')
Simply use :
"SELECT * FROM `trees` WHERE LOWER(trees.`title`) LIKE '%elm%'";
Or Use
"SELECT * FROM `trees` WHERE LCASE(trees.`title`) LIKE '%elm%'";
Both functions works same
I'm doing something like that.
Getting the values in lowercase and MySQL does the rest
$string = $_GET['string'];
mysqli_query($con,"SELECT *
FROM table_name
WHERE LOWER(column_name)
LIKE LOWER('%$string%')");
And For MySQL PDO Alternative:
$string = $_GET['string'];
$q = "SELECT *
FROM table_name
WHERE LOWER(column_name)
LIKE LOWER(?);";
$query = $dbConnection->prepare($q);
$query->bindValue(1, "%$string%", PDO::PARAM_STR);
$query->execute();
use ILIKE
SELECT * FROM trees WHERE trees.`title` ILIKE '%elm%';
it worked for me !!
Non-binary string comparisons (including LIKE) are case insensitive by default in MySql:
https://dev.mysql.com/doc/refman/en/case-sensitivity.html
I think this query will do a case insensitive search:
SELECT * FROM trees WHERE trees.`title` ILIKE '%elm%';
You don't need to ALTER any table. Just use the following queries, prior to the actual SELECT query that you want to use the wildcard:
set names `utf8`;
SET COLLATION_CONNECTION=utf8_general_ci;
SET CHARACTER_SET_CLIENT=utf8;
SET CHARACTER_SET_RESULTS=utf8;
well in mysql 5.5 , like operator is insensitive...so if your vale is elm or ELM or Elm or eLM or any other , and you use like '%elm%' , it will list all the matching values.
I cant say about earlier versions of mysql.
If you go in Oracle , like work as case-sensitive , so if you type like '%elm%' , it will go only for this and ignore uppercases..
Strange , but this is how it is :)
SELECT name
FROM gallery
WHERE CONVERT(name USING utf8) LIKE _utf8 '%$q%'
GROUP BY name COLLATE utf8_general_ci LIMIT 5
You must set up proper encoding and collation for your tables.
Table encoding must reflect the actual data encoding. What is your data encoding?
To see table encoding, you can run a query SHOW CREATE TABLE tablename
When I want to develop insensitive case searchs, I always convert every string to lower case before do comparasion
I've always solved like this:
SELECT * FROM trees WHERE LOWER( trees.title ) LIKE LOWER('%elm%');
For example if you want to search name like Raja not raja, Royal not royal etc, add BINARY before column name in WHERE clause.
SELECT name FROM person_tbl
WHERE BINARY name LIKE "R%";
I want to put a condition in my query where I have a column that should contain second position as an alphabet.
How to achieve this?
I've tried with _[A-Z]% in where clause but is not working. I've also tried [A-Z]%.
Any inputs please?
I think you want mysql query. like this
SELECT * FROM table WHERE column REGEXP '^.[A-Za-z]+$'
or sql server
select * from table where column like '_[a-zA-Z]%'
You can use regular expression matching in your query. For example:
SELECT * FROM `test` WHERE `name` REGEXP '^.[a-zA-Z].*';
That would match the name column from the test table against a regex that verifies if the second character is either a lowercase or uppercase alphabet letter.
Also see this SQL Fiddle for an example of data it does and doesn't match.
agree with #Gordon Linoff, your ('_[A-Z]%') should work.
if not work, kindly add some sample data with your question.
Declare #Table Table
(
TextCol Varchar(20)
)
Insert Into #Table(TextCol) Values
('23423cvxc43f')
,('2eD97S9')
,('sAgsdsf')
,('3Ss08008')
Select *
From #Table As t
Where t.TextCol Like '_[A-Z]%'
The use of '%[A-Z]%' suggests that you are using SQL Server. If so, you can do this using LIKE:
where col like '_[A-Z]%'
For LIKE patterns, _ represents any character. If the first character needs to be a digit:
where col like '[0-9][A-Z]%'
EDIT:
The above doesn't work in DB2. Instead:
where substr(col, 2, 1) between 'A' and 'Z'
I am writing a simple query in SQL Server:
SELECT *
FROM Table1
WHERE CONTAINS(Column1, 'MY')
but it doesn't return any results. While using like it returns results.
Is there any specific reason why the keyword 'MY' doesn't work?
Update:
If I use other keywords, it works, only the specific 'MY' seems to be that I cannot used. My column is already set into fulltext index. Also for performance purposes I prefer to use CONTAINS.
you could do something like
select * from Table1 where Column1 like '%MY%'
When you use linq you can use the statements like you use in C#. It will be translated to SQL, a language which database can execute. So, try something like this:
string sql = "SELECT * FROM Table1 WHERE Column1 like #Column1";
And in your command, try to add parameters to replace the #Column1
command.Parameters.AddWithValue("#Column1", "%MY%");
The % char, represents anything. So, if you want to do a command like StartWith like we do from string, just use MY%.
In my table I have a column of type nVarchar or nText
Suppose value of a this col is like this '... xxx yyy zzz ...'
I use SELECT to search table with this column
SELECT * FROM tbl_name WHERE col_name like '%xxx yyy%'
Since the I can't force users to enter words with my sequence I want to give same result with this query too:
SELECT * FROM tbl_name WHERE col_name like '%yyy xxx%'
It looks to me like you might want to consider normalizing your table. Specifically, if "yyy xxx" is the same as "xxx yyy", you're storing an array (or list or whatever you want to call it) in one column, which breaks first normal form. Normalize it so that each of those atoms (i.e. "xxx", "yyy") are stored separately and are related back to your original record. Then it's almost trivial to do the kind of thing you're looking to do.
You have to tokenize the user input into separate words inside your application code (not in sql) and then construct queries like
SELECT * FROM tbl_name WHERE
(col_name like '%yyy%') AND (col_name like '%xxx%') AND ...
Your best bet is to use both criteria, and "OR".
SELECT *
FROM tbl_name
WHERE (col_name like '%xxx yyy%')
OR (col_name like '%yyy xxx%');
I want to use the like command in a query to find specific results in Access. In the field that I want to utilize the like command has the wildcard (*) command in that field, which I want to search by. Is there a way around this? Example below:
SELECT *
FROM TABLE_NAME
WHERE FIELD_NAME LIKE '*'
Assuming you want to find columns that actually contain an asterisk (*) via the LIKE operator, here is an idea to try (see http://office.microsoft.com/en-us/access-help/using-wildcard-characters-in-string-comparisons-HP001032284.aspx )
SELECT *
FROM TABLE_NAME
WHERE FIELD_NAME LIKE '[*]'
The square brackets indicate that it's a literal asterisk to match, and not a wildcard.
* is not a wildcard in sql server like. So you can use:
SELECT *
FROM TABLE_NAME
WHERE FIELD_NAME LIKE '%*%' ;
If you want to search for actual wildcard %, you can change the wilcard to something else say &
SELECT *
FROM TABLE_NAME
WHERE FIELD_NAME LIKE '&%&' ESCAPE '&';