sql

SQL to get friends AND friends of friends of a user

My MySQL tables structure is like this. USER int id varchar username FRIEND_LIST int user_id int friend_id For each friend relationship I insert 2 records in FRIEND_LIST. If user 1 is friend of user 2 then the next rows are inserted into FRIEND_LIST 1,2 2,1 I want to get the friends and friends of friends of an specific user. The...

How to perform undirected graph processing from SQL data

I ran into the following problem in dynamically creating topics for our ActiveMQ system: I have a number of processes (M_1, ..., M_n), where n is not large, typically 5-10. Some of the processes will listen to the output of others, through a message queue; these edges are specified in an XML file, e.g. <link from="M1" to="M3"</link> <...

SQL Where question

Hi all, I have a question about case statements and nulls in a where clause. I want to do the following: Declare @someVar int = null select column1 as a from TestTable t where column1 = case when @someVar is not null then @someVar else column1 end Here is the problem: Let's say @someVar is null. Let's also say that column1 from T...

How to order by column with non-null values first in sql

I need to write a sql statement to select all users ordered by lastname, firstname. This is the part I know how to do :) What I don't know how to do is to order by non-null values first. Right now I get this: null, null null, null p1Last, p1First p2Last, p2First etc I need to get: p1Last, p1First p2Last, p2First null, null null,...

Is there any way to simplify a verbose SQL INSERT INTO(..) query?

I have a table with one id (autonumber) field and 50 other fields. The table is normalized, these are 50 material properties etc. I want to copy a record from this table into the same table - only the autoincrement id will be different. The query I am using now is INSERT INTO tableName (field1,field2,....field50) SELECT field1,field2,...

How to skip the invalid rows while inserting the data into Database

We have a statement., that is inserting some rows in a temporary table (say e.g., 10 rows), while inserting 5th row, it has some issue with one of the column format and giving an error and then it stopped inserting the rows. What I want is, it should skip the error rows and insert valid rows. For those error rows, it can skip that error...

Not able to add column value

I have project which contain 4 tables among these shedule table Session column i am not able to add vaue,,this table contain three foriegn key from two tables(in which single table has two foreign keys here) i added values here..Any one has any idea about this..Actually my intention is to remove the error "the insert statement conflict...

How can I get the rank of rows relative to total number of rows based on a field?

I have a scores table that has two fields: user_id score I'm fetching specific rows that match a list of user_id's. How can I determine a rank for each row relative to the total number of rows, based on score? The rows in the result set are not necessarily sequential (the scores will vary widely from one row to the next). I'm ...

SSIS: How to transfer data from table A to table B and then update table A flag column for each row

Hi, I need to crate a package in SSIS which will selectively transfer data from Table A to table B based on a flag in Table A and after the transfer update the flag in Table A. Please advice on the approach to this scenario and the different ways in which this can be done effectively. I would also like to mention that i have never wor...

How to rewrite long query?

Hi, I have the following 2 tables: items: id int primary key bla text events: id_items int num int when timestamp without time zone ble text composite primary key: id_items, num and want to select to each item the most recent event (the newest 'when'). I wrote an request, but I don't know if it could be written more efficient...

I need to insert multiple rows at once in sql server ..based on an iterative value

Hi friends, I want to insert 3 rows at a time in a table based on select statement.. consider the query insert into tblTemp ( a,b ) select a, b from tblTemp2 This lets me insert one row in tblTemp.. my requirement is to add 3 rows with iterative values a,a+1,a+2 for each b inserted. ...

select from varchar2 column with numeric value sometimes gives invalid number error

I'm trying to understand why, on some systems, I get an invalid number error message when I'm trying to select a value from a varchar2 column while on other systems I don't get the error while doing the exact same thing. The table is something like this: ID Column_1 Column_2 1 V text 2 D 1 3 D ...

Drawbacks of Dynamic Query in Sqlserver 2005 ?

I have using the many dynamic Query in my database for the procedures because my filter is not fix so i have taken @filter as parameter and pass in the procedure. Declare @query as varchar(8000) Declare @Filter as varchar(1000) set @query = 'Select * from Person.Address where 1=1 and ' + @Filter exec(@query) Like that my filter cont...

Can this sql query be simplified?

I have the following tables: Person, {"Id", "Name", "LastName"} Sports, {"Id" "Name", "Type"} SportsPerPerson, {"Id", "PersonId", "SportsId"} For my query I want to get all the Persons that excersise a specific Sport whereas I only have the Sports "Name" attribute at my disposal. To retrieve the correct rows I've figured out the followi...

SQL Query problem: How to merge two lists.

I have a base table of Participants and Answers, with the following structure: ParticipantId, BusUnitId, QuestionNum, Answer. In this table, QuestionNum ranges, say, from 1 to 6. I also have two other tables that sort of link QuestionNum to the actual question table, BusUnitQuestions, and ParticipantQuestions. For each QuestionNum, ...

Retrieve data from database

I need to use C# to get data from database(sql) and the data in database is updated every few seconds. So do I have to make a loop or there is a better way to do that? Is it possible that when database is updating, the program can wait until it finishes updating? thx! ...

Problem running oracle script from command line using sqlplus

I'm having a problem trying to run my sql script into oracle using sqlplus. The script just populates some dummy data: DECLARE role1Id NUMBER; user1Id NUMBER; role2Id NUMBER; user2Id NUMBER; role3Id NUMBER; user3Id NUMBER; perm1Id NUMBER; perm2Id NUMBER; perm3Id NUMBER; perm4Id NUMBER; perm5Id NUMBER; BEGIN INSE...

Logging into table in SQL Server trigger

I am coding SQL Server 2005 trigger. I want to make some logging during trigger execution, using INSERT statement into my log table. When there occurs error during execution, I want to raise error and cancel action that cause trigger execution, but not to lose log records. What is the best way to achieve this? Now my trigger logs everyt...

General many-to-many relationship problem ( Postgresql )

Hi, i have two tables: CREATE TABLE "public"."auctions" ( "id" VARCHAR(255) NOT NULL, "auction_value_key" VARCHAR(255) NOT NULL, "ctime" TIMESTAMP WITHOUT TIME ZONE NOT NULL, "mtime" TIMESTAMP WITHOUT TIME ZONE NOT NULL, CONSTRAINT "pk_XXXX2" PRIMARY KEY("id"), ); and CREATE TABLE "public"."auction_values" ( "id" NUMERIC DEFAU...

How to rollback a database deployment without losing new data?

My company uses virtual machines for our web/app servers. This allows for very easy rollbacks of a deployment if something goes wrong. However, if an app server deployment also requires a database deployment and we have to rollback I'm kind of at a loss. How can you rollback database schema changes without losing data? The only thing...