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Possible to do a MySQL foreign key to one of two possible tables?
...problem I have three tables; regions, countries, states. Countries can be inside of regions, states can be inside of regions. Regions are the top of the food chain.
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How to select rows with no matching entry in another table?
I'm doing some maintenance work on a database application and I've discovered that, joy of joys, even though values from one table are being used in the style of foreign keys, there's no foreign key constraints on the tables.
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List of all index & index columns in SQL Server DB
How do I get a list of all index & index columns in SQL Server 2005+? The closest I could get is:
30 Answers
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LAST_INSERT_ID() MySQL
I have a MySQL question that I think must be quite easy. I need to return the LAST INSERTED ID from table1 when I run the following MySql query:
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How to specify id when uses include in layout xml file
In my layout xml file, I have included other layout xml file (each
with a different android id).
11 Answers
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Android: View.setID(int id) programmatically - how to avoid ID conflicts?
I'm adding TextViews programmatically in a for-loop and add them to an ArrayList.
14 Answers
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How to find out client ID of component for ajax update/render? Cannot find component with expression
The following code is inspired from PrimeFaces DataGrid + DataTable Tutorials and put into a <p:tab> of a <p:tabView> residing in a <p:layoutUnit> of a <p:layout> . Here is the inner part of the code (starting from p:tab component); the outer part is trivial.
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PostgreSQL - fetch the row which has the Max value for a column
I'm dealing with a Postgres table (called "lives") that contains records with columns for time_stamp, usr_id, transaction_id, and lives_remaining. I need a query that will give me the most recent lives_remaining total for each usr_id
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How to get next/previous record in MySQL?
...want to be able to go from one to another by navigation via next/previous links. The problem is, that I don't know how to fetch record with nearest higher ID.
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What is the most efficient/elegant way to parse a flat table into a tree?
...eries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentId = t.Id
)
SELECT * FROM MyTree;
I tested recursiv...