Hi, is it possible to have unique value of a Text field of each post on a whole site (one unique value for each post/custom post type, similar to ID for each post).
Let say I have a Places custom post type and a Text field called Code.
For each place, I want to set a code (text+number) in the Code text field and two places can not have a same code.
Place 1 has code VNSG001
Place 2 has code VNSG002
Place 3 has code VNSG003
If I write VNSG001 or VNSG002 on the place 3 and click Publish/Update, it will show error and ask to change the value that doesn't exist.
Unfortunately, the plugin Meta Box does not support to check/validate the value in a field is unique or not. But you can use the post ID of WordPress itself (unique) to concatenate with your field value when printing out on the front end