What can be used when setting up a query for URL Creator/URL Integration? 

Simple and complex queries can be setup in URL Integration. The overall structure of the queries follows this format below:

[The database name of a field] <Any number of whitespaces> <relational operators> <Any number of whitespaces> "<Search criteria for the field type of the DocuWare field>"

An example of a database field name would be; 
[COMPANY_NAME] = "Peters Engineering"
Note: In addition, the field name needs to be as it is in the database, they are also case sensitive.
If not sure how to obtain the database name for an index field, refer to the following; 

Depending on the data types we search on, there are a few things which need to be taken into consideration. 

When searching on numeric fields, the query will work the same as it would for letters. For example, [INVOICE_NUMBER] = "12345"

For searches containing a date, the date information must be entered in a non-language specific format "YYYY-MM-DD", so that the query will always work correctly. For example, [DUE_DATE] = "2021-04-21"

When queries contain one or more quotation marks, a backslash must be placed in front of the quotation mark.
This will remove the meta-meaning of the quotation marks. An example of this would be, [SUBJECT] = "So-called \" Web 2.0 \""

Possible relational operators include: <=, >=, <, >, =, and LIKE
The LIKE operator is only valid for text fields. If the LIKE operator is used, the search criterion must contain at least one *

Possible logical operators include: AND, OR, NOT.
There must always be at least one space before and after each logical operator. This also applies to LIKE.

Setting up Complex Queries:
To setup a Complex Query, you would specify the fields you want to search by and include the necessary logical operators to put it altogether. 
An example would be; 

[COMPANY] = "Phone Wizard" AND [DEPARTMENT] = "Accounting" AND [STATUS] = "to be approved"

KBA is applicable for both On-premise and Cloud systems.