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Oracle-is there any way to use multiple parameter in wildcard [closed]
Closed 9 years ago.
I want to find out the name from database which names are start with A to M or is there any way to use multiple parameter in wildcard (LIKE) for eg-
SELECT name
FROM database
WHERE name LIKE (I want to search A to M here);
Try:
select ...
where ... substr(name,1,1) between 'A' and 'M'
Possibly you want to:
select ...
where ... upper(substr(name,1,1)) between 'A' and 'M'
This does have the advantage of potentially being indexable, although the index would probably only be used for much smaller ranges.
Use REGEXP_LIKE, refer here for more in detail.
Try like this,
SELECT name FROM database WHERE REGEXP_LIKE(name, '^[A-M]');
There's no need to use substr or regexp_like or like.
The following statement is much simpler (and has the advantage that it can use an ordinary index):
SELECT name FROM database WHERE name >= 'A' AND name < 'N';
This query works on the basis that 'AA' > 'A' and all strings starting with 'M' sort before 'N'.
As far as index usage is concerned, I'm presuming that since you want half of the alphabet as the first letter that you will also be querying for half of the total number of rows and hence Oracle will prefer a full-table scan.
SELECT name FROM database WHERE name LIKE '[A-M]'
Related
My question is simple.
In a DB2 Database, I have my table
Table (Id integer, name varchar)
I want to select entries which names like 'ac1%' or 'ac2%' or 'ac3%', so which names match regex
'^ac[123]*'
Is there any method to have this select query without write :
WHERE name LIKE 'ac1%' OR name LIKE 'ac2%' OR name LIKE 'ac2%'
Probably the most efficient method is:
where name >= 'ac1' and
name < 'ac4'
You can also use regular expressions:
where regexp_like(name, '^ac[1-3]')
Depending on your Db2-server platform (Z/OS, i-Series, Linux/Unix/Windows) and Db2-version, you can use REGEXP_LIKE function. This allows regular expressions in SQL.
See documentation and examples here.
i think below will work cause REGEXP_LIKE(col,'[0-9]{3}-[0-9]{3}-[0-9]{2}') will always return true if col contain any of 0 to 9 value
SELECT * FROM table1
WHERE REGEXP_LIKE(name,'[1-3]')
I want to look for values in variable/column which start with 'S' and has 'gg' in between.
For instance Staggered is a word which starts with alphabet S and has gg in between the word.
so what sql query to write to get the result.
Due to the fact that you did not provide much meta information (which database?), I'll just show the following:
SELECT * FROM <table>
WHERE <columnname> LIKE 'S%gg%';
Good luck :)
As the target database is not mentioned, I will answer with Oracle syntax:
select *
from TABLE_NAME
where COL_NAME like 'S%gg%'
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 am trying to write code that allows me to check if there are any cases of a particular pattern inside a table.
The way I am currently doing is with something like
select count(*)
from database.table
where column like (some pattern)
and seeing if the count is greater than 0.
I am curious to see if there is any way I can speed up this process as this type of pattern finding happens in a loop in my query and all I need to know is if there is even one such case rather than the total number of cases.
Any suggestions will be appreciated.
EDIT: I am running this inside a Teradata stored procedure for the purpose of data quality validation.
Using EXISTS will be faster if you don't actually need to know how many matches there are. Something like this would work:
IF EXISTS (
SELECT *
FROM bigTbl
WHERE label LIKE '%test%'
)
SELECT 'match'
ELSE
SELECT 'no match'
This is faster because once it finds a single match it can return a result.
If you don't need the actual count, the most efficient way in Teradata will use EXISTS:
select 1
where exists
( select *
from database.table
where column like (some pattern)
)
This will return an empty result set if the pattern doesn't exist.
In terms of performance, a better approach is to:
select the result set based on your pattern;
limit the result set's size to 1.
Check whether a result was returned.
Doing this prevents the database engine from having to do a full table scan, and the query will return as soon as the first matching record is encountered.
The actual query depends on the database you're using. In MySQL, it would look something like:
SELECT id FROM database.table WHERE column LIKE '%some pattern%' LIMIT 1;
In Oracle it would look like this:
SELECT id FROM database.table WHERE column LIKE '%some pattern%' AND ROWNUM = 1;
I am wondering if there is a way to write the SQL so that it would return me a result as usual but now, on the first row that would return also the attribute names.
To explain what I mean:
say you have a table "test" which has 2 attributes "id" and "name":
id name
1 nik
2 tst
query:
SELECT * FROM test;
produces:
1 nik
2 tst
but what I want it to return is this:
id name
1 nik
2 tst
Is this possible?
edit: I am using PostreSQL
You cannot return the names and the actual column values in a single result unless you give up on the real datatypes (which is probably not what you want).
Your example mixes character data and numeric data in the id column and Postgres will (rightfully) refuse to return such a result set.
Edit:
I tested the "union" solution given e.g. by JNK and it fails (as expected) on Postgres, Oracle and SQL Server precisely because of the non-matching datatypes. MySQL follows it's usual habits of not throwing errors and simply converts everything to characters.
Extremely generic answer since you don't provide an RDBMS:
SELECT id, name FROM(
SELECT 'id' as 'id', 'name' as 'name', 1 as 'Rank'
UNION ALL
SELECT *, 2 as 'Rank' FROM test) as X
ORDER BY [RANK]
EDIT
Thanks to Martin for pointing out the need for the ORDER BY
Assuming you are on SQL Server, you can get the column names of a specific table by using this query:
select column_name 'Column Name', data_type 'Data Type'
from information_schema.columns
where table_name = 'putYourTableNameHere'
Then, you'll have to UNION your things together.
I agree with OMG Ponies above, the way to get this meta-data is usually from the interface you use.
for example the Perl DBI module has a method fetchrow_hashref where the columns of the returned row are returned as an associative array (hash) where the colnames are the keys.
print $ref->{'name'}; # would print nik or tst
Update:
I had forgotten to add that some of these interface layers have a method that return s the col names and you could use that instead of adding the names into your result set.
The DBI method you'd use would be $sth->{NAMES}->[0] would return the first column name.
Depending on your tools / technique, but here are a couple:
If you're using SSMS (Sql-Server), and want to copy/paste your results with the column headers:
Query Window -->
R-Click
Results -->
Grid or Text -->
Check-mark the 'Include column headers in the result set' option
If you're using Sql-Server, you can query meta-tables (sys.columns, etc.)
If you're using an ASP.NET databound control, you usually have access to methods or properties (sqldatareader.getname(i), etc.)
Anyway -- just depends on the layer you're trying to get the names from -- if these above don't help, then edit / re-tag your question so we can focus on whatever tool you're wanting to use to do this.
EDIT for PostgresSQL
If you're using PostgresSQL, you can query meta-tables (information_schema.columns, etc.)