Two questions about date conversion in cypher

[haidkang]

I have two questions about date conversion in cypher.

First,
There is SQL in Oracle :
SELECT TO_CHAR(SYSDATE, 'D') FROM DUAL;

The SQL returns a number from 1 (sun) to 7 (sat)
Does Neo4j have a cypher function to replace it?

Second
If the arguemnts is put 1 (sun) ~ 7 (sat) as below SQL to return the NEXT day of the week in Oracle
SELECT NEXT_DAY(SYSDATE, 1) FROM DUAL

Is there a cypher query to replace it?

Thank you.

[glilienfield]

Neo4j has a lot of support for date/time and duration entities. You can find a description in the following section of the cypher manual:

Neo4j Graph Data Platform

Temporal (Date/Time) values - Neo4j Cypher Manual

Cypher has built-in support for handling temporal values, and the underlying database supports storing these temporal values as properties on nodes and relationships.

To address your two questions, the following should work:

1. date() returns the current date, which is an object with many attributes. dayOfWeek is one that returns the number of the weekday. The numbers start with Monday as the beginning of a week, so if you want Sunday to be the beginning, you can use the following query to transform the day of week to start with Sunday as 1.

return (date().dayOfWeek+1)%7

2. You can add a duration of any amount to a date to get a new date. The following works to add 1 day to the current date:

return date()+duration({days:1})

Review the manual for see all of the capabilities. There are many.

[haidkang]

In the second case, I created the query as shown below with your information and hints.

WITH date.truncate('week', date(), {dayOfWeek: 1}) as outday,
date() as today
RETURN
CASE
WHEN outday < today then outday + duration({days:7})
ELSE outday
END AS thedate

Thank you.

[glilienfield · Accepted solution]

Oops, the above formula for transforming the day of the week is incorrect, as Saturday gets mapped to '0', so ignore this suggestion.

If this is needed, the simplest method I can think of is a literal mapping.

with [0,2,3,4,5,6,7,1] as weekDayMapping, date().dayOfWeek as day
return weekDayMapping[day]

[haidkang]

Thank you for your solution.