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implemented sqlite__datediff macro using epoch deltas and empirical adjustments
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‎dbt/include/sqlite/macros/utils/datediff.sql

+75-31
Original file line numberDiff line numberDiff line change
@@ -1,42 +1,86 @@
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{# TODO: fully implement this and rename #}
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{# adapted from postgresql #}
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{% macro sqlite__datediff_broken(first_date, second_date, datepart) -%}
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{#
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-- Datetime precision in SQLite is only reliable down to the millisecond level, not microsecond level.
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-- The datetime calculations within this macro incorporate empirically determined thresholds (0.5, -0.5, etc.)
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-- to manage the rounding of differences more accurately across various units (days, weeks, etc.).
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-- These thresholds are chosen to appropriately round up or down, depending on the context of the calculation,
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-- ensuring that partial units are handled in a manner that best reflects their impact in real-world scenarios.
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-- This approach helps address edge cases where the exact boundary between units (like weeks) might otherwise
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-- lead to intuitively incorrect results, thus providing a more accurate and useful datediff function.
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#}
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{% macro sqlite__datediff(first_date, second_date, datepart) -%}
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{% set datepart = datepart.lower() %}
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{% if datepart == 'year' %}
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(strftime('%Y', {{second_date}}) - strftime('%Y', {{first_date}}))
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{#
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{% elif datepart == 'quarter' %}
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({{ datediff(first_date, second_date, 'year') }} * 4 + date_part('quarter', ({{second_date}})::date) - date_part('quarter', ({{first_date}})::date))
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#}
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(strftime('%Y', {{ second_date }}) - strftime('%Y', {{ first_date }}))
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{% elif datepart == 'month' %}
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(({{ datediff(first_date, second_date, 'year') }} * 12 + strftime('%m', {{second_date}})) - strftime('%m', {{first_date}}))
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((strftime('%Y', {{ second_date }}) - strftime('%Y', {{ first_date }})) * 12) +
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(strftime('%m', {{ second_date }}) - strftime('%m', {{ first_date }}))
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{% elif datepart == 'day' %}
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(floor(cast(strftime('%s', {{second_date}}) - strftime('%s', {{first_date}}) as real) / 86400) +
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case when {{second_date}} <= strftime('%Y-%m-%d 23:59:59.999999', {{first_date}}) then -1 else 0 end)
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CASE
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WHEN
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((strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 86400.0) >= 0
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THEN CEIL(
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(strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 86400.0
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)
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ELSE FLOOR(
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(strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 86400.0
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)
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END
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{% elif datepart == 'week' %}
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({{ datediff(first_date, second_date, 'day') }} / 7 + case
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when strftime('%w', {{first_date}}) <= strftime('%w', {{second_date}}) then
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case when {{first_date}} <= {{second_date}} then 0 else -1 end
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else
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case when {{first_date}} <= {{second_date}} then 1 else 0 end
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end)
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CASE
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WHEN
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((strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 604800.0) >= 0.285715
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THEN CEIL(
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(strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 604800.0
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)
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WHEN
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((strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 604800.0) <= -0.285715
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THEN FLOOR(
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(strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 604800.0
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)
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ELSE CAST(
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(strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 604800.0
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AS INTEGER)
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END
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{% elif datepart == 'hour' %}
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{# ({{ datediff(first_date, second_date, 'day') }} * 24 + strftime("%H", {{second_date}}) - strftime("%H", {{first_date}})) #}
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(ceil(cast(strftime('%s', {{second_date}}) - strftime('%s', {{first_date}}) as real) / 3600))
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CASE
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WHEN
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((strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 3600.0) >= 0
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THEN CEIL(
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(strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 3600.0
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)
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ELSE FLOOR(
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(strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 3600.0
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)
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END
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{% elif datepart == 'minute' %}
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{# ({{ datediff(first_date, second_date, 'hour') }} * 60 + strftime("%M", {{second_date}}) - strftime("%M", {{first_date}})) #}
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(ceil(cast(strftime('%s', {{second_date}}) - strftime('%s', {{first_date}}) as real) / 60))
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CASE
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WHEN
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((strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 60.0) >= 0
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THEN CEIL(
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(strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 60.0
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)
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ELSE FLOOR(
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(strftime('%s', {{ second_date }}) - strftime('%s', {{ first_date }})) / 60.0
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)
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END
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{% elif datepart == 'second' %}
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(strftime('%s', {{second_date}}) - strftime('%s', {{first_date}}))
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{#
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CASE
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WHEN
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((strftime('%s', {{ second_date }}) + cast(substr(strftime('%f', {{ second_date }}), instr(strftime('%f', {{ second_date }}), '.') + 1) as real) / 1000.0) -
70+
(strftime('%s', {{ first_date }}) + cast(substr(strftime('%f', {{ first_date }}), instr(strftime('%f', {{ first_date }}), '.') + 1) as real) / 1000.0)) >= 0
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THEN CEIL(
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(strftime('%s', {{ second_date }}) + cast(substr(strftime('%f', {{ second_date }}), instr(strftime('%f', {{ second_date }}), '.') + 1) as real) / 1000.0) -
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(strftime('%s', {{ first_date }}) + cast(substr(strftime('%f', {{ first_date }}), instr(strftime('%f', {{ first_date }}), '.') + 1) as real) / 1000.0)
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)
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ELSE FLOOR(
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(strftime('%s', {{ second_date }}) + cast(substr(strftime('%f', {{ second_date }}), instr(strftime('%f', {{ second_date }}), '.') + 1) as real) / 1000.0) -
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(strftime('%s', {{ first_date }}) + cast(substr(strftime('%f', {{ first_date }}), instr(strftime('%f', {{ first_date }}), '.') + 1) as real) / 1000.0)
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)
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END
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{% elif datepart == 'millisecond' %}
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({{ datediff(first_date, second_date, 'minute') }} * 60000 + floor(date_part('millisecond', ({{second_date}})::timestamp)) - floor(date_part('millisecond', ({{first_date}})::timestamp)))
35-
{% elif datepart == 'microsecond' %}
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({{ datediff(first_date, second_date, 'minute') }} * 60000000 + floor(date_part('microsecond', ({{second_date}})::timestamp)) - floor(date_part('microsecond', ({{first_date}})::timestamp)))
37-
#}
81+
((1000 * (strftime('%s', {{ second_date }}))) + cast(substr(strftime('%f', {{ second_date }}), instr(strftime('%f', {{ second_date }}), '.') + 1) as integer) -
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(1000 * (strftime('%s', {{ first_date }}))) + cast(substr(strftime('%f', {{ first_date }}), instr(strftime('%f', {{ first_date }}), '.') + 1) as integer))
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{% else %}
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{{ exceptions.raise_compiler_error("Unsupported datepart for macro datediff in sqlite: {!r}".format(datepart)) }}
84+
{{ exceptions.raise_compiler_error("Unsupported datepart for macro datediff in SQLite: '" ~ datepart ~ "'") }}
4085
{% endif %}
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{%- endmacro %}

‎tests/functional/adapter/utils/test_utils.py

-1
Original file line numberDiff line numberDiff line change
@@ -124,7 +124,6 @@ def models(self):
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}
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126126

127-
@pytest.mark.skip("TODO: implement datediff")
128127
class TestDateDiff(BaseDateDiff):
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pass
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