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Foreign Key to non-primary key
I have a table which holds data, and one of those rows needs to exist in another table. So, I want a foreign key to maintain referential integrity.
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Splitting string into multiple rows in Oracle
...str(t.error, '[^,]+', 1, levels.column_value)) as error
from
temp t,
table(cast(multiset(select level from dual connect by level <= length (regexp_replace(t.error, '[^,]+')) + 1) as sys.OdciNumberList)) levels
order by name
EDIT:
Here is a simple (as in, "not in depth") explanation of t...
PostgreSQL function for last inserted ID
In PostgreSQL, how do I get the last id inserted into a table?
10 Answers
10
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What is the maximum length of a table name in Oracle?
What are the maximum length of a table name and column name in Oracle?
12 Answers
12
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MySQL: #126 - Incorrect key file for table
...is can be caused by a full ramdisk when doing things like altering a large table if you have a ramdisk configured. You can temporarily comment out the ramdisk line to allow such operations if you can't increase the size of it.
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Adding 'serial' to existing column in Postgres
I have a small table (~30 rows) in my Postgres 9.0 database with an integer ID field (the primary key) which currently contains unique sequential integers starting at 1, but which was not created using the 'serial' keyword.
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When increasing the size of VARCHAR column on a large table could there be any problems?
...er 2008 and I need to make a VARCHAR field bigger, from (200 to 1200) on a table with about 500k rows. What I need to know is if there are any issues I have not considered.
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How do I find which transaction is causing a “Waiting for table metadata lock” state?
I am trying to perform some DDL on a table and SHOW PROCESSLIST results in a " Waiting for table metadata lock " message.
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MySQL ON vs USING?
...fferences are noteworthy:
ON is the more general of the two. One can join tables ON a column, a set of columns and even a condition. For example:
SELECT * FROM world.City JOIN world.Country ON (City.CountryCode = Country.Code) WHERE ...
USING is useful when both tables share a column of the exac...
Programmatically creating Markdown tables in R with KnitR
...ver, one thing that I'm not seeing is an easy way to print data frames and tables using Markdown formatting (sort of like xtable , but with Markdown instead of LaTeX or HTML). I know that I can just embed the HTML output from xtable, but I was wondering if there were any Markdown-based solutions?
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