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ALTER TABLE to add a composite primary key
I have a table called provider . I have three columns called person , place , thing . There can be duplicate persons, duplicate places, and duplicate things, but there can never be a dupicate person-place-thing combination.
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Display names of all constraints for a table in Oracle SQL
I have defined a name for each of the constraint for the multiple tables that I have created in Oracle SQL.
6 Answers
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What is the difference between LR, SLR, and LALR parsers?
...s of LR parsers, but what is the actual difference as far as their parsing tables are concerned?
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Illegal mix of collations MySQL Error
...BASE your_database_name CHARACTER SET utf8 COLLATE utf8_general_ci;
ALTER TABLE your_table_name CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci;
MySQL sneaks swedish in there sometimes for no sensible reason.
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Find the number of columns in a table
It is possible to find the number of rows in a table:
19 Answers
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Insert new column into table in sqlite?
I have a table with columns name , qty , rate . Now I need to add a new column COLNew in between the name and qty columns. How do I add a new column in between two columns?
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How can I drop all the tables in a PostgreSQL database?
How can I drop all tables in PostgreSQL, working from the command line?
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iOS 7 - How to display a date picker in place in a table view?
In WWDC 2013 video, Apple suggests displaying picker in place in a table view in iOS 7. How to insert and animate a view between table view cells?
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Delete with Join in MySQL
Here is the script to create my tables:
13 Answers
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What's the difference between a catalog and a schema in a relational database?
...if you query the information_schema views, you'll find that values in the "table_catalog" column map to the name of a database.
If you find your platform using catalog in a broader way than any of these three definitions, it might be referring to something broader than a database--a database cl...