Marek: Created page with "Group by day of the week (using arithmetic).

schema:gisq

We can use modular arithmetic to calculate the day of the week. We hap..."

2012-07-17T15:17:19Z

Created page with "Group by day of the week (using arithmetic). <div class='ht'> <div class=params>schema:gisq</div> <div> We can use modular arithmetic to calculate the day of the week. We hap..."

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Group by day of the week (using arithmetic).
<div class='ht'>
<div class=params>schema:gisq</div>
<div>
We can use modular arithmetic to calculate the day of the week.

We happen to know that 20 May 1962 was a Sunday. We calculate
the number of days from that day and take mod 7 value. This tells
us the day of the week: 0 is Sunday, 1 is Monday...
</div>

<source lang=sql class='tidy'></source>
<source lang=sql class='setup'></source>

<source lang='sql' class='def'>
</source>

<source lang='sql' class='def e-oracle'>
SELECT MOD(wk - TO_DATE('1962-05-20','YYYY-MM-DD'),7),
COUNT(song)
FROM gisq.totp
GROUP BY MOD(wk - TO_DATE('1962-05-20','YYYY-MM-DD'),7)
</source>

<div class="ecomm e-oracle" style="display: none">Dates may be subtracted. The answer is in units of days.</div>
</div>
{{DATE and TIME ref}}

Date arithmetics - Revision history

Marek: Created page with "Group by day of the week (using arithmetic). schema:gisq We can use modular arithmetic to calculate the day of the week. We hap..."

Marek: Created page with "Group by day of the week (using arithmetic).

schema:gisq

We can use modular arithmetic to calculate the day of the week. We hap..."