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LISTAGG in Oracle to return distinct values
...tagg(distinct the_column, ',') within group (order by the_column)
from the_table
18c and earlier:
select listagg(the_column, ',') within group (order by the_column)
from (
select distinct the_column
from the_table
) t
If you need more columns, something like this might be what you are lo...
What is hashCode used for? Is it unique?
...n index for an object
in a collection.
The GetHashCode method is suitable for use in hashing algorithms and
data structures such as a hash table.
The default implementation of the GetHashCode method does not
guarantee unique return values for different objects. Furthermore, the
.NE...
搭建高可用mongodb集群（二）—— 副本集 - 大数据 & AI - 清泛网 - 专注C/...
....168.1.136:27017 would veto with 'I don't think 192.168.1.138:27017 is electable'
Sun Dec 29 20:26:31.059 [rsHealthPoll] replset info 192.168.1.137:27017 thinks that we are down
Sun Dec 29 20:26:31.059 [rsHealthPoll] replSet member 192.168.1.137:27017 is now in state STARTUP2
Sun Dec 29 20:26:31....
Downloading MySQL dump from command line
...mp -u [uname] -p --all-databases > all_db_backup.sql
If it's specific tables within a DB, then:
$ mysqldump -u [uname] -p db_name table1 table2 > table_backup.sql
You can even go as far as auto-compressing the output using gzip (if your DB is very big):
$ mysqldump -u [uname] -p db...
How do I set a background-color for the width of text, not the width of the entire element, using CS
...
display:table is a better choice... to avoid the problem highlighted in the comments section in the next reply. display:inline will concatenate <h1> and <h2> to be in same line.... when they are originally in next lines.
...
How do I (or can I) SELECT DISTINCT on multiple columns?
I need to retrieve all rows from a table where 2 columns combined are all different. So I want all the sales that do not have any other sales that happened on the same day for the same price. The sales that are unique based on day and price will get updated to an active status.
...
Why do I get a “Null value was assigned to a property of primitive type setter of” error message whe
...he solution is replace primitive type with primitive wrapper class in your tableName.java file.
Such as:
@Column(nullable=true, name="client_os_id")
private Integer client_os_id;
public int getClient_os_id() {
return client_os_id;
}
public void setClient_os_id(int clientOsId) {
client_os_...
Best dynamic JavaScript/JQuery Grid [closed]
...
Free:
Gijgo Grid
Backgrid.js
Flexigrid
jqGridView
Ingrid
SlickGrid
DataTables
Shield UI Lite Grid
Paid:
Fancy Grid
jQuery Grid
jqxGrid
Shield UI Grid
The best entries in my opinion are Flexigrid and jQuery Grid.
sh...
Removing a model in rails (reverse of “rails g model Title…”)
...oy' on that model, it will delete the migration file, but not the database table. So before run
bundle exec rake db:rollback
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How to drop columns using Rails migration
What's the syntax for dropping a database table column through a Rails migration?
20 Answers
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