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How Can I Set the Default Value of a Timestamp Column to the Current Timestamp with Laravel Migratio
... use DB::raw() to set CURRENT_TIMESTAMP as a default value for a column:
$table->timestamp('created_at')->default(DB::raw('CURRENT_TIMESTAMP'));
This works flawlessly on every database driver.
New shortcut
As of Laravel 5.1.25 (see PR 10962 and commit 15c487fe) you can use the new useCurr...
Best practices for SQL varchar column length [closed]
Every time is set up a new SQL table or add a new varchar column to an existing table, I am wondering one thing: what is the best value for the length .
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MySQL SELECT only not null values
... give UNKNOWN with NULL on either side of the expression.)
SELECT *
FROM table
WHERE YourColumn IS NOT NULL;
Just for completeness I'll mention that in MySQL you can also negate the null safe equality operator but this is not standard SQL.
SELECT *
FROM table
WHERE NOT (YourColumn <=> N...
Create a nonclustered non-unique index within the CREATE TABLE statement with SQL Server
...ossible to create a primary key or unique index within a SQL Server CREATE TABLE statement. Is it possible to create a non-unique index within a CREATE TABLE statement?
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Error Code: 1005. Can't create table '…' (errno: 150)
...T(11) or TINYINT. You may want to confirm the field size using SHOW CREATE TABLE because Query Browser will sometimes visually show just INTEGER for both INT(10) and INT(11). You should also check that one is not SIGNED and the other is UNSIGNED. They both need to be exactly the same.
One of the key...
Mapping many-to-many association table with extra column(s)
My database contains 3 tables:
User and Service entities have many-to-many relationship and are joined with the SERVICE_USER table as follows:
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How to reset AUTO_INCREMENT in MySQL?
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You can reset the counter with:
ALTER TABLE tablename AUTO_INCREMENT = 1
For InnoDB you cannot set the auto_increment value lower or equal to the highest current index. (quote from ViralPatel):
Note that you cannot reset the counter to a value less than or ...
How do I change the data type for a column in MySQL?
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http://dev.mysql.com/doc/refman/5.1/en/alter-table.html
ALTER TABLE tablename MODIFY columnname INTEGER;
This will change the datatype of given column
Depending on how many columns you wish to modify it might be best to generate a script, or use some kind of mysql clie...
PostgreSQL - how to quickly drop a user with existing privileges
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Doing: CREATE TABLE foo(bar SERIAL); ALTER TABLE foo OWNER TO postgres; CREATE USER testuser; GRANT ALL ON foo TO testuser; DROP USER testuser gave the error messages: ERROR: role "testuser" cannot be dropped because some objects depend...
There is no ViewData item of type 'IEnumerable' that has the key 'xxx'
...e is the source SelectList.
What happened with my error was:
Because the table containing the drop down lists was in a partial view and the ViewData had been changed and no longer contained the SelectList I had referenced, the HtmlHelper (instead of throwing an error) tried to find the SelectList...