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In which case do you use the JPA @JoinTable annotation?
In which case do you use the JPA @JoinTable annotation?
5 Answers
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How do I add a foreign key to an existing SQLite table?
I have the following table:
9 Answers
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SQL - many-to-many table primary key
...is guaranteed unique (assuming your col1 and col2 values in the referenced tables are unique) and a separate index on (col2,col1) will catch those cases where the opposite order would execute faster. The surrogate is a waste of space.
You won't need indexes on the individual columns since the table...
Design patterns or best practices for shell scripts [closed]
... functions, like in this example code
# avoid double inclusion
if test "${Table__imported+defined}" == "defined"
then
return 0
fi
Table__imported=1
readonly Table__NoException=""
readonly Table__ParameterException="Table__ParameterException"
readonly Table__MySqlException="Table__MySqlExceptio...
How to get a list of column names on Sqlite3 database?
...
PRAGMA table_info(table_name);
will get you a list of all the column names.
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How do I list all tables in a schema in Oracle SQL?
How do i list all tables in a schema in Oracle SQL?
14 Answers
14
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How do I alter the position of a column in a PostgreSQL database table?
...ly defines column
order based on the attnum column of
the pg_attribute table. The only way
to change column order is either by
recreating the table, or by adding
columns and rotating data until you
reach the desired layout.
That's pretty weak, but in their defense, in standard SQL, the...
What is the purpose of setting a key in data.table?
I am using data.table and there are many functions which require me to set a key (e.g. X[Y] ). As such, I wish to understand what a key does in order to properly set keys in my data tables.
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How to import a single table in to mysql database using command line
...atabase using command line, but now my pain area is how to import a single table with its data to the existing database using command line.
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How can I set the max-width of a table cell using percentages?
The above does not work. How can I set the max-width of a table cell using percentages?
4 Answers
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