Zenkit

Bulk actions allow you to make changes to multiple items inside of a collection at once. You can decide which items to change by either selecting them individually, or filtering for certain items. If you want to make changes to multiple items, here's how to select them: 

Selecting multiple items

To select multiple items in any view, hold down the Alt key then click on the items you want to select.
 

To deselect an item, click it again while holding Alt. 

In Table view you can additionally use the checkbox in the top left corner of the table to select all items or click and drag your mouse across the table. If a filter is applied, it will only select the items that match the filter.

Please note that in Linux Alt+Click is a shortcut to move the window, so you have to choose to allow Zenkit to override that function in order for the select feature to work. Here's how in Ubuntu. 

Using the bulk actions menu

The bulk actions menu is found in the top right hand corner, and shows you how many items you have selected.
 

"Deselect all" is pretty self-explanatory, clicking this will deselect all items.

"Reverse selection" will select every other item in your collection, except the ones you had originally selected.

"Duplicate items" will duplicate all the items you have selected, including labels, assigned members, and any additional data you've added to them.

"Archive items" will immediately archive all selected items.

Last but not least, "Bulk action" is the real powerhouse tool that lets you perform a certain action on all selected items. Bulk actions, used in combination with a filter and then selecting all items (from the table view, or by clicking on the collection name, then the ... icon and selecting "Bulk action"), gives you a powerful way to manage the details of a large but specific number of items. Lets dig into the details... 

Bulk action

When you click "Bulk action" from the bulk actions menu, a popup appears. Each of the four actions lets you set, add, remove or replace certain values, depending on the field you choose to change.

The only fields you won't be able to change in this way are the formula and file fields. To edit a formula field, you just need to edit the formula in the field properties popup. Files need to be added or removed from items on an individual basis.

Set

"Set" sets the value of a field. This means that it will overwrite any previously set value. It works in a slightly different way for each of the field types.

Text, Links & Numbers
For text, link and number fields, you just need to type in the new text, link or number that you'd like to set for your multiple items.

References, Labels & Members

Depending on the permissions given to the particular field, you can set one or more values. For example, if the members field only allows you to set one member, you will only be able to set one. If your reference field allows you to create new references, you will also be able to do that here. Just start typing in the 'Value to set' field to start searching for members and references, or choose from the labels displayed to set them.

Dates
For date fields, you will be shown the calendar when you click in the box under 'Value to set'. Just set a date as you normally would. You can also set a time if your date field allows it.

Checkbox
For a checkbox you can either select the checkbox or not. Simple!

Add 

"Add" allows you to add more information to data that already exists in a field. It will not overwrite the existing field, just add to it. This option isn't available for all fields.

Text & Links
Any text you add will append text that already exists in the field. For now, any text you add will be appended directly on to the end of the existing text, without a space in between. For example, if you have 'www.example.com' written in a text field, you could add '/newpage' to change the link to 'www.example.com/newpage'.

Numbers
Numbers don't follow the same rule here. If you add a number, it will actually 'add' that number, instead of just appending it to the existing number. For example, if the number field currently contains '10' and you add '4' the field will be updated to show '14' instead of '104'.

References, Labels and Members
Depending on the rules you've set for the particular field you're adding to, you can select additional references or labels from the existing ones, or create new ones. You can search for and select new members to add if your members field allows more than one member to be added.

Exceptions
The fields you cannot add to are dates and checkboxes. You will also not be able to add to member and label fields that specify only one label or member. Use the Set function for those.

Remove

For most fields, remove works as a 'find and delete' function. It will not remove all data from the fields, just the part of it that you specify. This option is not available for all fields.

Text & Links
For text and link fields, 'remove' will find a string of text inside your fields and remove it. This can be a letter, number, word, or entire sentence, and it will be removed even if it's surrounded by other text and characters.
For example, if you want to remove the 'www.' from all of your links for a cleaner look but still usable url, just type 'www.' into the 'Remove value' box. 'www.google.com' thus becomes 'google.com'.

A word of caution: be as precise as you can! If you ask Zenkit to remove just one letter, then you will remove that letter from everywhere in the text.

For example, say you want to get rid of the extra 'r' at the end of this phrase: 'Red lorry, yellow lorryr'. If you ask Zenkit to just remove 'r', then you'll end up with 'ed loy, yellow loy'. You're better off using the replace function for tasks like this!

Numbers
Just as with "add", "remove" works slightly differently for number fields. Removing a number will subtract it from the number currently in the field. For example, if you remove '24' from a field that contains '1024', it will be updated to show '1000' and not '10'.

References, Labels & Members
For these fields, the remove function will allow you to remove references, labels and members from items that currently have some selected. You will be able to search for and remove references or members, or select labels to remove from the display.

Exceptions
You cannot remove data from a checkbox or date field.

Replace

This can also be thought of as "search and replace", and works for every field type.

Text & Links
Here is where the replace function shines. You can search for an exact string of text, and replace it with another, even if that string is surrounded by other text and characters. Again, it pays to be very precise.
For example, you could replace the '.com' in link fields containing 'www.example.com/newpage.html' with '.de' to create 'www.example.de/newpage.html'.

In a normal text field you could use this to replace whole words or phrases, or even correct spelling mistakes: replace 'wrold' with 'world' to fix 'Hello world!'.

Numbers
As with "add" and "remove", numbers are treated as whole numbers, and not as their composite parts (or as strings). This means that you cannot replace one part of a number, but need to replace a whole number: You can replace '5000' with '6000', but you cannot replace '5' with '6' to change 5000 to 6000.

Dates
To replace dates, just choose the date you want to replace from the calendar, and then choose a replacement date. This works for times as well.

References, Labels & Members
To replace references, labels and members, just search for and select the reference, label or member you want to change, then do the same for the one you want to replace it with.

This also works if you want to replace multiple labels or members. For example, you could re-label items labelled with "To Do" with both "In Progress" and "Bottleneck", should you need to.

Or you could replace the members 'Sarah' and 'Rob' with 'Aisha' if the task needs to transfer from two hands to one.

Checkbox
The checkbox is a special case. Since it's binary, there's only one option. If you select the checkbox, it will replace all unselected checkboxes with selected ones. If you leave the checkbox unselected, it will replace all selected checkboxes with unselected ones.