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Reorder / reset auto increment primary key
I have a MySQL table with an auto increment primary key. I deleted some rows in the middle of the table. Now I have, for example, something like this in the ID column: 12, 13, 14, 19, 20. I deleted the 15, 16, 17 and 18 rows.
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What is the difference between JOIN and UNION?
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Joins and Unions can be used to combine data from one or more tables. The difference lies in how the data is combined.
In simple terms, joins combine data into new columns. If two tables are joined together, then the data from the first table is shown in one set of column alongside t...
How to list of all the tables defined for the database when using active record?
How do I get a list of all the tables defined for the database when using active record?
5 Answers
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SQL Add foreign key to existing column
If I am using the following SQL command in SQL Server 2008 to update a table with a foreign key constraint:
6 Answers
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How to reset a single table in rails?
...rd::Base.connection.execute("DELETE from sqlite_sequence where name = 'yourtablename'")
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Table name as variable
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For static queries, like the one in your question, table names and column names need to be static.
For dynamic queries you should generate the full SQL dynamically, and use sp_executesql to execute it.
Here is an example of a script used to compare data between the same ta...
Can you have if-then-else logic in SQL? [duplicate]
I need to do select data from a table based on some kind of priority like so:
7 Answers
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How do I select an entire row which has the largest ID in the table?
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You could use a subselect:
SELECT row
FROM table
WHERE id=(
SELECT max(id) FROM table
)
Note that if the value of max(id) is not unique, multiple rows are returned.
If you only want one such row, use @MichaelMior's answer,
SELECT row from table ORDER BY ...
How to import CSV file data into a PostgreSQL table?
...ite a stored procedure that imports data from a CSV file and populates the table?
18 Answers
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Disable all table constraints in Oracle
How can I disable all table constrains in Oracle with a single command?
This can be either for a single table, a list of tables, or for all tables.
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