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What does mysql error 1025 (HY000): Error on rename of './foo' (errorno: 150) mean?
..., something like this:
CONSTRAINT region_ibfk_1 FOREIGN
KEY (country_id) REFERENCES
country (id) ON DELETE NO
ACTION ON UPDATE NO ACTION
Now simply issue an:
alter table region drop foreign key
region_ibfk_1;
And finally an:
alter table region drop column
country_id;
And ...
mysql Foreign key constraint is incorrectly formed error
I have two tables, table1 is the parent table with a column ID and table2 with a column IDFromTable1 (not the actual name) when I put a FK on IDFromTable1 to ID in table1 I get the error Foreign key constraint is incorrectly formed error . I would like to delete table 2 record if tab...
Maven: Non-resolvable parent POM
... the same directory (same project). But this doesn't solve this error. Any idea how to fix it?
– Praneeth Peiris
Apr 5 '19 at 9:26
...
What's wrong with foreign keys?
...t get Orphaned Rows
you can get nice "on delete cascade" behavior, automatically cleaning up tables
knowing about the relationships between tables in the database helps the Optimizer plan your queries for most efficient execution, since it is able to get better estimates on join cardinality.
FKs gi...
How to remove padding around buttons in Android?
In my Android app, I have this layout:
17 Answers
17
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how does array[100] = {0} set the entire array to 0?
...ory.
int foo(void)
{
char array[100] = {0};
...
}
In this case at every call of the function foo you will have a hidden memset.
The code above is equivalent to
int foo(void)
{
char array[100];
memset(array, 0, sizeof(array));
....
}
and if you omit the initializer your array will contain ra...
What's the difference between TRUNCATE and DELETE in SQL
...to be faster than a DELETE.
Various system-specific issues have to be considered, as detailed below.
Statement type
Delete is DML, Truncate is DDL (What is DDL and DML?)
Commit and Rollback
Variable by vendor
SQL*Server
Truncate can be rolled back.
PostgreSQL
Truncate can be rolled back...
how to read System environment variable in Spring applicationContext
...ng 3.0 adds Spring Expression Language.
You can use
<util:properties id="dbProperties"
location="classpath:config_#{systemProperties['env']}/db.properties" />
Combined with java ... -Denv=QA should solve your problem.
Note also a comment by @yiling:
In order to access system env...
How to rename a single column in a data.frame?
... answered May 10 '13 at 20:33
Side_0o_EffectSide_0o_Effect
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ORA-01882: timezone region not found
...egion=false in file oracle/jdbc/defaultConnectionProperties.properties (inside the jar). Found this solution here
Lastly, one can add -Doracle.jdbc.timezoneAsRegion=false to the command line, or AddVMOption -Doracle.jdbc.timezoneAsRegion=false in config files that use this notation
...