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I have a component that retrieves data from database based on the keys provided.
However I want my java application to get all the data for all keys in a single database hit to fasten up things.
I can use 'in' clause when I have only one key.
While working on more than one key I can use below query in oracle
SELECT * FROM <table_name>
where (value_type,CODE1) IN (('I','COMM'),('I','CORE'));
which is similar to writing
SELECT * FROM <table_name>
where value_type = 1 and CODE1 = 'COMM'
and
SELECT * FROM <table_name>
where value_type = 1 and CODE1 = 'CORE'
together
However, this concept of using 'in' clause as above is giving below error in 'SQL server'
ERROR:An expression of non-boolean type specified in a context where a condition is expected, near ','.
Please let know if their is any way to achieve the same in SQL server.
This syntax doesn't exist in SQL Server. Use a combination of And and Or.
SELECT *
FROM <table_name>
WHERE
(value_type = 1 and CODE1 = 'COMM')
OR (value_type = 1 and CODE1 = 'CORE')
(In this case, you could make it shorter, because value_type is compared to the same value in both combinations. I just wanted to show the pattern that works like IN in oracle with multiple fields.)
When using IN with a subquery, you need to rephrase it like this:
Oracle:
SELECT *
FROM foo
WHERE
(value_type, CODE1) IN (
SELECT type, code
FROM bar
WHERE <some conditions>)
SQL Server:
SELECT *
FROM foo
WHERE
EXISTS (
SELECT *
FROM bar
WHERE <some conditions>
AND foo.type_code = bar.type
AND foo.CODE1 = bar.code)
There are other ways to do it, depending on the case, like inner joins and the like.
If you have under 1000 tuples you want to check against and you're using SQL Server 2008+, you can use a table values constructor, and perform a join against it. You can only specify up to 1000 rows in a table values constructor, hence the 1000 tuple limitation. Here's how it would look in your situation:
SELECT <table_name>.* FROM <table_name>
JOIN ( VALUES
('I', 'COMM'),
('I', 'CORE')
) AS MyTable(a, b) ON a = value_type AND b = CODE1;
This is only a good idea if your list of values is going to be unique, otherwise you'll get duplicate values. I'm not sure how the performance of this compares to using many ANDs and ORs, but the SQL query is at least much cleaner to look at, in my opinion.
You can also write this to use EXIST instead of JOIN. That may have different performance characteristics and it will avoid the problem of producing duplicate results if your values aren't unique. It may be worth trying both EXIST and JOIN on your use case to see what's a better fit. Here's how EXIST would look,
SELECT * FROM <table_name>
WHERE EXISTS (
SELECT 1
FROM (
VALUES
('I', 'COMM'),
('I', 'CORE')
) AS MyTable(a, b)
WHERE a = value_type AND b = CODE1
);
In conclusion, I think the best choice is to create a temporary table and query against that. But sometimes that's not possible, e.g. your user lacks the permission to create temporary tables, and then using a table values constructor may be your best choice. Use EXIST or JOIN, depending on which gives you better performance on your database.
Normally you can not do it, but can use the following technique.
SELECT * FROM <table_name>
where (value_type+'/'+CODE1) IN (('I'+'/'+'COMM'),('I'+'/'+'CORE'));
A better solution is to avoid hardcoding your values and put then in a temporary or persistent table:
CREATE TABLE #t (ValueType VARCHAR(16), Code VARCHAR(16))
INSERT INTO #t VALUES ('I','COMM'),('I','CORE')
SELECT DT. *
FROM <table_name> DT
JOIN #t T ON T.ValueType = DT.ValueType AND T.Code = DT.Code
Thus, you avoid storing data in your code (persistent table version) and allow to easily modify the filters (without changing the code).
I think you can try this, combine and and or at the same time.
SELECT
*
FROM
<table_name>
WHERE
value_type = 1
AND (CODE1 = 'COMM' OR CODE1 = 'CORE')
What you can do is 'join' the columns as a string, and pass your values also combined as strings.
where (cast(column1 as text) ||','|| cast(column2 as text)) in (?1)
The other way is to do multiple ands and ors.
I had a similar problem in MS SQL, but a little different. Maybe it will help somebody in futere, in my case i found this solution (not full code, just example):
SELECT Table1.Campaign
,Table1.Coupon
FROM [CRM].[dbo].[Coupons] AS Table1
INNER JOIN [CRM].[dbo].[Coupons] AS Table2 ON Table1.Campaign = Table2.Campaign AND Table1.Coupon = Table2.Coupon
WHERE Table1.Coupon IN ('0000000001', '0000000002') AND Table2.Campaign IN ('XXX000000001', 'XYX000000001')
Of cource on Coupon and Campaign in table i have index for fast search.
Compute it in MS Sql
SELECT * FROM <table_name>
where value_type + '|' + CODE1 IN ('I|COMM', 'I|CORE');
I've been playing around with the sample on Jeff' Server blog to compare two tables to find the differences.
In my case the tables are a backup and the current data. I can get what I want with this SQL statement (simplified by removing most of the columns). I can then see the rows from each table that don't have an exact match and I can see from which table they come.
SELECT
MIN(TableName) as TableName
,[strCustomer]
,[strAddress1]
,[strCity]
,[strPostalCode]
FROM
(SELECT
'Old' as TableName
,[JAS001].[dbo].[AR_CustomerAddresses].[strCustomer]
,[JAS001].[dbo].[AR_CustomerAddresses].[strAddress1]
,[JAS001].[dbo].[AR_CustomerAddresses].[strCity]
,[JAS001].[dbo].[AR_CustomerAddresses].[strPostalCode]
FROM
[JAS001].[dbo].[AR_CustomerAddresses]
UNION ALL
SELECT
'New' as TableName
,[JAS001new].[dbo].[AR_CustomerAddresses].[strCustomer]
,[JAS001new].[dbo].[AR_CustomerAddresses].[strAddress1]
,[JAS001new].[dbo].[AR_CustomerAddresses].[strCity]
,[JAS001new].[dbo].[AR_CustomerAddresses].[strPostalCode]
FROM
[JAS001new].[dbo].[AR_CustomerAddresses]) tmp
GROUP BY
[strCustomer]
,[strAddress1]
,[strCity]
,[strPostalCode]
HAVING
COUNT(*) = 1
This Stack Overflow Answer gives me a much cleaner SQL query but does not tell me from which table the rows come.
SELECT * FROM [JAS001new].[dbo].[AR_CustomerAddresses]
UNION
SELECT * FROM [JAS001].[dbo].[AR_CustomerAddresses]
EXCEPT
SELECT * FROM [JAS001new].[dbo].[AR_CustomerAddresses]
INTERSECT
SELECT * FROM [JAS001].[dbo].[AR_CustomerAddresses]
I could use the first version but I have many tables that I need to compare and I think that there has to be an easy way to add the source table column to the second query. I've tried several things and googled to no avail. I suspect that maybe I'm just not searching for the correct thing since I'm sure it's been answered before.
Maybe I'm going down the wrong trail and there is a better way to compare the databases?
Could you use the following setup to accomplish your goal?
SELECT 'New not in Old' Descriptor, *
FROM
(
SELECT * FROM [JAS001new].[dbo].[AR_CustomerAddresses]
EXCEPT
SELECT * FROM [JAS001].[dbo].[AR_CustomerAddresses]
) a
UNION
SELECT 'Old not in New' Descriptor, *
FROM
(
SELECT * FROM [JAS001].[dbo].[AR_CustomerAddresses]
EXCEPT
SELECT * FROM [JAS001new].[dbo].[AR_CustomerAddresses]
) b
You can't add the table name there because union, except, and intersection all compare all columns. This means you can't differentiate between them by adding the table name to the query. A group by gives you control over what columns are considered in finding duplicates so you can exclude the table name.
To help you with the large number of tables you need to compare you could write a sql query off the metadata tables that hold table names and columns and generate the sql commands dynamically off those values.
Derive one column using table names like below
SELECT MIN(TableName) as TableName
,[strCustomer]
,[strAddress1]
,[strCity]
,[strPostalCode]
,table_name_came
FROM
(SELECT 'Old' as TableName
,[JAS001].[dbo].[AR_CustomerAddresses].[strCustomer]
,[JAS001].[dbo].[AR_CustomerAddresses].[strAddress1]
,[JAS001].[dbo].[AR_CustomerAddresses].[strCity]
,[JAS001].[dbo].[AR_CustomerAddresses].[strPostalCode]
,'[JAS001].[dbo].[AR_CustomerAddresses]' as table_name_came
FROM [JAS001].[dbo].[AR_CustomerAddresses]
UNION ALL
SELECT 'New' as TableName
,[JAS001new].[dbo].[AR_CustomerAddresses].[strCustomer]
,[JAS001new].[dbo].[AR_CustomerAddresses].[strAddress1]
,[JAS001new].[dbo].[AR_CustomerAddresses].[strCity]
,[JAS001new].[dbo].[AR_CustomerAddresses].[strPostalCode]
,'[JAS001new].[dbo].[AR_CustomerAddresses]' as table_name_came
FROM [JAS001new].[dbo].[AR_CustomerAddresses]
) tmp
GROUP BY [strCustomer]
,[strAddress1]
,[strCity]
,[strPostalCode]
,table_name_came
HAVING COUNT(*) = 1
select * into #transacTbl from tmpTrans
insert
select
(case when tmpT.TranStatus = 10
then(
select ID, 'Returned')
else(
select ID, 'GoodSale')
end)
from
(
select * from MainTransacSource
) as tmpT
I want to be able to insert the details of a transaction into a different table with a label if it is a returned or good sale/transaction. I did this to avoid the cursor so please avoid giving a solution using a cursor.
I know the code looks good but what I'm experiencing is that, the case statement only returns one value via subquery.
This is a simplified version of the code; I have at least 6 types of cases and should be able to insert by ROW. I hate to think that I have to repeat each case per column because the actual number of columns is about 38.
You may suggest another work-around if this doesn't fit the logic. Of course, without a cursor.
Without access to your tables and not knowing more about what precisely you want to acheive, try something like this:
select * into #transacTbl from tmpTrans
insert
select tmpT.ID,
(case when tmpT.TranStatus = 10
then 'Returned'
else 'GoodSale'
end)
from
(select * from MainTransacSource) as tmpT <OR simply MainTransacSource tmpT (maybe)>
Cheers.
I know I can write a query that will return all rows that contain any number of values in a given column, like so:
Select * from tbl where my_col in (val1, val2, val3,... valn)
but if val1, for example, can appear anywhere in my_col, which has datatype varchar(300), I might instead write:
select * from tbl where my_col LIKE '%val1%'
Is there a way of combing these two techniques. I need to search for some 30 possible values that may appear anywhere in the free-form text of the column.
Combining these two statements in the following ways does not seem to work:
select * from tbl where my_col LIKE ('%val1%', '%val2%', 'val3%',....)
select * from tbl where my_col in ('%val1%', '%val2%', 'val3%',....)
What would be useful here would be a LIKE ANY predicate as is available in PostgreSQL
SELECT *
FROM tbl
WHERE my_col LIKE ANY (ARRAY['%val1%', '%val2%', '%val3%', ...])
Unfortunately, that syntax is not available in Oracle. You can expand the quantified comparison predicate using OR, however:
SELECT *
FROM tbl
WHERE my_col LIKE '%val1%' OR my_col LIKE '%val2%' OR my_col LIKE '%val3%', ...
Or alternatively, create a semi join using an EXISTS predicate and an auxiliary array data structure (see this question for details):
SELECT *
FROM tbl t
WHERE EXISTS (
SELECT 1
-- Alternatively, store those values in a temp table:
FROM TABLE (sys.ora_mining_varchar2_nt('%val1%', '%val2%', '%val3%'/*, ...*/))
WHERE t.my_col LIKE column_value
)
For true full-text search, you might want to look at Oracle Text: http://www.oracle.com/technetwork/database/enterprise-edition/index-098492.html
A REGEXP_LIKE will do a case-insensitive regexp search.
select * from Users where Regexp_Like (User_Name, 'karl|anders|leif','i')
This will be executed as a full table scan - just as the LIKE or solution, so the performance will be really bad if the table is not small. If it's not used often at all, it might be ok.
If you need some kind of performance, you will need Oracle Text (or some external indexer).
To get substring indexing with Oracle Text you will need a CONTEXT index. It's a bit involved as it's made for indexing large documents and text using a lot of smarts. If you have particular needs, such as substring searches in numbers and all words (including "the" "an" "a", spaces, etc) , you need to create custom lexers to remove some of the smart stuff...
If you insert a lot of data, Oracle Text will not make things faster, especially if you need the index to be updated within the transactions and not periodically.
No, you cannot do this. The values in the IN clause must be exact matches. You could modify the select thusly:
SELECT *
FROM tbl
WHERE my_col LIKE %val1%
OR my_col LIKE %val2%
OR my_col LIKE %val3%
...
If the val1, val2, val3... are similar enough, you might be able to use regular expressions in the REGEXP_LIKE operator.
Yes, you can use this query (Instead of 'Specialist' and 'Developer', type any strings you want separated by comma and change employees table with your table)
SELECT * FROM employees em
WHERE EXISTS (select 1 from table(sys.dbms_debug_vc2coll('Specialist', 'Developer')) mt
where em.job like ('%' || mt.column_value || '%'));
Why my query is better than the accepted answer: You don't need a CREATE TABLE permission to run it. This can be executed with just SELECT permissions.
In Oracle you can use regexp_like as follows:
select *
from table_name
where regexp_like (name, '^(value-1|value-2|value-3....)');
The caret (^) operator to indicate a beginning-of-line character &
The pipe (|) operator to indicate OR operation.
This one is pretty fast :
select * from listofvalue l
inner join tbl on tbl.mycol like '%' || l.value || '%'
Just to add on #Lukas Eder answer.
An improvement to avoid creating tables and inserting values
(we could use select from dual and unpivot to achieve the same result "on the fly"):
with all_likes as
(select * from
(select '%val1%' like_1, '%val2%' like_2, '%val3%' like_3, '%val4%' as like_4, '%val5%' as like_5 from dual)
unpivot (
united_columns for subquery_column in ("LIKE_1", "LIKE_2", "LIKE_3", "LIKE_4", "LIKE_5"))
)
select * from tbl
where exists (select 1 from all_likes where tbl.my_col like all_likes.united_columns)
I prefer this
WHERE CASE WHEN my_col LIKE '%val1%' THEN 1
WHEN my_col LIKE '%val2%' THEN 1
WHEN my_col LIKE '%val3%' THEN 1
ELSE 0
END = 1
I'm not saying it's optimal but it works and it's easily understood. Most of my queries are adhoc used once so performance is generally not an issue for me.
select * from tbl
where exists (select 1 from all_likes where all_likes.value = substr(tbl.my_col,0, length(tbl.my_col)))
You can put your values in ODCIVARCHAR2LIST and then join it as a regular table.
select tabl1.* FROM tabl1 LEFT JOIN
(select column_value txt from table(sys.ODCIVARCHAR2LIST
('%val1%','%val2%','%val3%')
)) Vals ON tabl1.column LIKE Vals.txt WHERE Vals.txt IS NOT NULL
You don't need a collection type as mentioned in https://stackoverflow.com/a/6074261/802058. Just use an subquery:
SELECT *
FROM tbl t
WHERE EXISTS (
SELECT 1
FROM (
SELECT 'val1%' AS val FROM dual
UNION ALL
SELECT 'val2%' AS val FROM dual
-- ...
-- or simply use an subquery here
)
WHERE t.my_col LIKE val
)
Is it possible to have a statement like
SELECT "Hello world"
WHERE 1 = 1
in SQL?
The main thing I want to know, is can I SELECT from nothing, ie not have a FROM clause.
It's not consistent across vendors - Oracle, MySQL, and DB2 support dual:
SELECT 'Hello world'
FROM DUAL
...while SQL Server, PostgreSQL, and SQLite don't require the FROM DUAL:
SELECT 'Hello world'
MySQL does support both ways.
Try this.
Single:
SELECT * FROM (VALUES ('Hello world')) t1 (col1) WHERE 1 = 1
Multi:
SELECT * FROM (VALUES ('Hello world'),('Hello world'),('Hello world')) t1 (col1) WHERE 1 = 1
more detail here : http://modern-sql.com/use-case/select-without-from
In Oracle:
SELECT 'Hello world' FROM dual
Dual equivalent in SQL Server:
SELECT 'Hello world'
Here is the most complete list of database support of dual from https://blog.jooq.org/tag/dual-table/:
In many other RDBMS, there is no need for dummy tables, as you can
issue statements like these:
SELECT 1;
SELECT 1 + 1;
SELECT SQRT(2);
These are the RDBMS, where the above is generally possible:
H2
MySQL
Ingres
Postgres
SQLite
SQL Server
Sybase ASE
In other RDBMS, dummy tables are required, like in Oracle. Hence,
you’ll need to write things like these:
SELECT 1 FROM DUAL;
SELECT 1 + 1 FROM DUAL;
SELECT SQRT(2) FROM DUAL;
These are the RDBMS and their respective dummy tables:
DB2: SYSIBM.DUAL
Derby: SYSIBM.SYSDUMMY1
H2: Optionally supports DUAL
HSQLDB: INFORMATION_SCHEMA.SYSTEM_USERS
MySQL: Optionally supports DUAL
Oracle: DUAL
Sybase SQL Anywhere: SYS.DUMMY
Ingres has no DUAL, but would actually need it as in Ingres you cannot
have a WHERE, GROUP BY or HAVING clause without a FROM clause.
In SQL Server type:
Select 'Your Text'
There is no need for the FROM or WHERE clause.
You can. I'm using the following lines in a StackExchange Data Explorer query:
SELECT
(SELECT COUNT(*) FROM VotesOnPosts WHERE VoteTypeName = 'UpMod' AND UserId = #UserID AND PostTypeId = 2) AS TotalUpVotes,
(SELECT COUNT(*) FROM Answers WHERE UserId = #UserID) AS TotalAnswers
The Data Exchange uses Transact-SQL (the SQL Server proprietary extensions to SQL).
You can try it yourself by running a query like:
SELECT 'Hello world'
There is another possibility - standalone VALUES():
VALUES ('Hello World');
Output:
column1
Hello World
It is useful when you need to specify multiple values in compact way:
VALUES (1, 'a'), (2, 'b'), (3, 'c');
Output:
column1 column2
1 a
2 b
3 c
DBFiddle Demo
This syntax is supported by SQLite/PostgreSQL/DB LUW/MariaDB 10.3.
In Firebird, you can do this:
select "Hello world" from RDB$DATABASE;
RDB$DATABASE is a special table that always has one row.
I think it is not possible. Theoretically: select performs two sorts of things:
narrow/broaden the set (set-theory);
mapping the result.
The first one can be seen as a horizontal diminishing opposed to the where-clause which can be seen as a vertical diminishing. On the other hand, a join can augment the set horizontally where a union can augment the set vertically.
augmentation diminishing
horizontal join/select select
vertical union where/inner-join
The second one is a mapping. A mapping, is more a converter. In SQL it takes some fields and returns zero or more fields. In the select, you can use some aggregate functions like, sum, avg etc. Or take all the columnvalues an convert them to string. In C# linq, we say that a select accepts an object of type T and returns an object of type U.
I think the confusion comes by the fact that you can do: select 'howdy' from <table_name>. This feature is the mapping, the converter part of the select. You are not printing something, but converting! In your example:
SELECT "
WHERE 1 = 1
you are converting nothing/null into "Hello world" and you narrow the set of nothing / no table into one row, which, imho make no sense at all.
You may notice that, if you don't constrain the number of columns, "Hello world" is printed for each available row in the table. I hope, you understand why by now. Your select takes nothing from the available columns and creates one column with the text: "Hello world".
So, my answer is NO. You can't just leave out the from-clause because the select always needs table-columns to perform on.
In Standard SQL, no. A WHERE clause implies a table expression.
From the SQL-92 spec:
7.6 "where clause"
Function
Specify a table derived by the
application of a "search condition" to
the result of the preceding "from
clause".
In turn:
7.4 "from clause"
Function
Specify a table derived from one or more named tables.
A Standard way of doing it (i.e. should work on any SQL product):
SELECT DISTINCT 'Hello world' AS new_value
FROM AnyTableWithOneOrMoreRows
WHERE 1 = 1;
...assuming you want to change the WHERE clause to something more meaningful, otherwise it can be omitted.
For ClickHouse, the nothing is system.one
SELECT 1 FROM system.one
I know this is an old question but the best workaround for your question is using a dummy subquery:
SELECT 'Hello World'
FROM (SELECT name='Nothing') n
WHERE 1=1
This way you can have WHERE and any clause (like Joins or Apply, etc.) after the select statement since the dummy subquery forces the use of the FROM clause without changing the result.
For DB2:
`VALUES('Hello world')`
You can do multiple "rows" as well:
`VALUES('Hello world'),('Goodbye world');`
You can even use them in joins as long as the types match:
VALUES(1,'Hello world')
UNION ALL
VALUES(2,'Goodbye world');
I'm using firebird
First of all, create a one column table named "NoTable" like this
CREATE TABLE NOTABLE
(
NOCOLUMN INTEGER
);
INSERT INTO NOTABLE VALUES (0); -- You can put any value
now you can write this
select 'hello world' as name
from notable
you can add any column you want to be shown