union

Does table1 UNION ALL table2 guarantee output order table1, table2?

SELECT a FROM b UNION ALL SELECT a FROM c UNION ALL SELECT a FROM d Does UNION ALL guarantee to print out records from tables b, c, d in that order? I.e., no records from c before any from b. This question is not for a specific DBMS. ...

Error in Union trying to sort null at end in sql server

Hi, I am trying to sort my database in some particular order, but I want all null's at the end, so I am selecting all values with not null, and then selecting all values WITH null, and trying to join them with Union.. like: SELECT * FROM preferences WHERE preferenceOrder IS NOT NULL ORDER BY preferenceOr...

Simplify complex union all in PostgreSQL

I have very complex query in PostgreSQL that unions several tables, that all have common set of fields we want to union. currently we're pregenerating this query. I have seen solution to this using UNPIVOT and I'm wondering if it's possible to do this in PostgreSQL flavour of SQL. What I have is something like SELECT a,b,c FROM a UNION...

C++: Union vs Bitwise operators

Hi, I have two char's and I want to "stitch" them bitwise together. For example: char c1 = 11; // 0000 1011 char c2 = 5; // 0000 0101 short int si = stitch(c1, c2); // 0000 1011 0000 0101 So, what I first tried was with bitwise operators: short int stitch(char c1, char c2) { return (c1 << 8) | c2; } But this doesn't work: I'm...

C#: How to fit a structure in an int64 ?

Question: I need to fit the following structure into an int64 day 9 bit (0 to 372) year 8 bit (2266-2010 = 256 y) seconds 17 bit (24*60*60=86400 s) hostname 12 bit (2^12=4096) random 18 bit (2^18=262144) How do I make such a structure fit in an int64 ? All items are numberic, and of the specified bit size. ...

Templated << friend not working when in interrelationship with other templated union types.

While working on my basic vector library, I've been trying to use a nice syntax for swizzle-based printing. The problem occurs when attempting to print a swizzle of a different dimension than the vector in question. In GCC 4.0, I originally had the friend << overloaded functions (with a body, even though it duplicated code) for every dim...

polymorphism in c and buffers

I have this union: typedef union Message { message_base base; message_with_parameters parameters; reply_message reply; buffer_t *buffer; // can't figure out what to put here } message; message_with_parameters has a message_base as the first field and reply_message has a message_wit...

Union query and C++

I use MySQL database and C++ programming language. In my database there are 20 tables. I produce different messages from these tables. All tables include dateTime columns and I want to sort produced messages. I did it by using union. But query is so long. Do you think it has another way or my way is correct. Thans a lot. ...

IQueryable member methods not behaving?

This is my code: IQueryable<Car> list = new List<Car>().AsQueryable<Car>(); foreach (TreeNode node in DataHierarchyTree.CheckedNodes) { var a = from c in ContextDB.Cars where c.CarID == Int32.Parse(node.Value) select c; list.Union(a.ToList()); } CarGridView.DataSourc...

xpath 'or' behaving like union ('|') with xmllib2

I have XML documents like: <rootelement> <myelement>test1</myelement> <myelement>test2</myelement> <myelement type='specific'>test3</myelement> </rootelement> I'd like to retrieve the specific myelement, and if it's not present, then the first one. So I write: /rootelement/myelement[@type='specific' or position()=1] The XPath spec ...

Mysql num rows on multiple tables using UNION

Hi all, I'm trying to find number of rows for two tables: Example 1 returns 81 (which is wrong). SELECT p_id FROM j_posts INNER JOIN j_blogs ON p_blog_id = b_id && b_approved = 1 WHERE p_is_draft = 0 UNION SELECT ep_id FROM j_external_posts INNER JOIN j_blogs ON ep_blog_id = b_id && b_approved = 1 I have then tried to split up th...

Is there a way to access individual bits with a union?

I am writing a C program. I want a variable that I can access as a char but I can also access the specific bits of. I was thinking I could use a union like this... typedef union { unsigned char status; bit bits[8]; }DeviceStatus; but the compiler doesn't like this. Apparently you can't use bits in a structure. So what can I ...

Need Help Translating SQL Server UNION Syntax to LINQ

Hi. I have the below SQL which works just fine: SELECT Message, CreateDate, AccountId, AlertTypeId FROM dbo.Alerts UNION SELECT TOP (100) PERCENT Status, CreateDate, AccountId, (SELECT 10 AS Expr1) AS AlertTypeId FROM dbo.StatusUpdates WHERE AccountId = PassedInParameter ORDER BY Cre...

Using union and order by clause in mysql

I want to use order by with union in mysql query. I am fetching different types of record based on different criteria from a table based on distance for a search on my site. The first select query returns data related to the exact place search . The 2nd select query returns data related to distance within 5 kms from the place searched. T...

Is there a neater linq way to 'Union' a single item?

If I have two sequences and I want to process them both together, I can union them and away we go. Now lets say I have a single item I want to process between the two sequencs. I can get it in by creating an array with a single item, but is there a neater way? i.e. var top = new string[] { "Crusty bread", "Mayonnaise" }; string fillin...

UNION syntax in Cakephp

Anyone knows a good way to make UNION query in CakePHP? I would like to avoid using $this->query();. With two tables t1, t2: SELECT * FROM t1 LEFT JOIN t2 ON t1.id = t2.id UNION SELECT * FROM t1 RIGHT JOIN t2 ON t1.id = t2.id With three tables t1, t2, t3: SELECT * FROM t1 LEFT JOIN t2 ON t1.id = t2.id LEFT JOIN t3 ON t2.id = t3.id U...

SQL UNION with conditions and recursive

Hi, i'm having problems with 2 query for my DB class. I have one table "clients" with this columns: name | id | date | points | REFERRAL --------------------------------------------- daniel | 123456 | 01-01-01 | 50 | 321321 jack | 321321 | 01-01-01 | 30 | 555555 Note that daniel was refered by jack 1) With the ID...

Get a complete list of unique values from multiple columns in multiple tables

Back story if you want it: I have an odd situation. An organization affiliated with my own provides us with a database that we use heavily; a few other organizations also use it, but our records are easily more than 90% of the total. We have a web frontend for data entry that is connected to the live database, but we only get the backe...

Appending one sql query with another.

Hi, I have a datareader that binds a sql select (with 10 columns from table1) , i want to append another with 5 different cols from table2 to this first sql select, i can't do UNION as it has different number of columns, (one query has 10, another returns 5 cols). Is there any other way of implementing this, via mysql? Also i need to ...

Question about unions and heap allocated memory.

I was trying to use a union to so I could update the fields in one thread and then read allfields in another thread. In the actual system, I have mutexes to make sure everything is safe. The problem is with fieldB, before I had to change it fieldB was declared like field A and C. However, due to a third party driver, fieldB must be allig...