I have a set of date ranges consisting of both partially and fully overlapping dates, like this: Using T-SQL, I would like to create a new set of data, per user, with eliminated overlapping data, extending ranges and removing redundant data where needed, resulting in something like this: Cursors are fine if needed, but if I can do without them
Default value not populating in migration with Rails and Postgresql
I am currently trying to run this migration: class AddDroppedProjectsCountToUser < ActiveRecord::Migration def self.up add_column :users, :dropped_projects, :integer, {:default=>0, :…
Insert with Hibernate native query does not work for java.util.Date
I am using Hibernate JPA and Spring with a Mysql database and I want to insert using a SQL statement like this: But after running it I get the following error: Could someone help me on this please? PS. I am aware of using hibernate in non-native way, but I need to use native way. I am also of insert
SQL query: select five most commented posts from different blogs
I have a following tables Blogs(id) and Posts(id, blog_id, comment_count) I need to select five most commented posts from different blogs. It’s quite easy to do with a function, but is it possible to …
SQL Inserting Data into table
I have a SQL table, let’s call it “Table A”, which has several rows of data. I then have a temp table called “Table b” that has one row of data. I want to be able to do a sql insert so that if Table A …
How do you avoid column name conflicts?
I was recently assigned a task of creating an auction system. During my work, I met numerous occasions where my SQL queries that contained joins failed to execute due to ambiguous column names. …
ORA-00054 Resource busy when dropping table
Can somebody explain this error? ORA-00054: Resource busy and aquire with NOWAIT specified This error came in a DROP TABLE. Because of it, procedures and packages are not getting compiled.
SQL Views “WITH CASCADE CHECK OPTION” Behaivor?
I can’t find any reference, or documentation on this. Does the condition clause read x = 1 AND y = 1 in case of UPDATE/INSERT on view2? Answer OK, so maybe have a look at WITH CASCADED CHECK OPTION and it’s example and Defining Views It would seem that the WITH CASCADE option does enforce all view criteria.
How to Count or Sum the String columns values
I have employees attendance table from date 1 to 31 with column names like 1, 2, 3, 4 5…..31 and datatype is nVarchar(5) I am adding values in those columns (P, H, A) for example: P = Present A = …
Detect if value is number in MySQL
Is there a way to detect if a value is a number in a MySQL query? Such as SELECT * FROM myTable WHERE isANumber(col1) = true