[Abde1rahman1]

Fixes #39531

DateTime.Ticks on SQLite was translated to CAST((julianday(x) - 1721425.5) * 864000000000.0 AS INTEGER), which has two problems:

• The multiplication produces a REAL around 6e17, beyond the range where a double represents integers exactly, so even whole-millisecond values come back wrong (e.g. ...10.123 gave 630298926101229952 instead of 630298926101230000).
• SQLite's date and time functions only keep milliseconds, so the remaining fractional digits are lost.

As a result, a query such as Where(e => e.DateTime.Ticks == ticks) could miss rows whose value has a fractional second.

Changes

DateTime columns are now translated using integer arithmetic for the whole seconds, with the fractional digits read directly from the stored text (yyyy-MM-dd HH:mm:ss.FFFFFFF), which is exact to the tick:

(CAST(strftime('%s', substr("b"."DateTime", 1, 19)) AS INTEGER) + 62135596800) * 10000000
    + CAST(substr(substr("b"."DateTime", 21) || '0000000', 1, 7) AS INTEGER)

The fraction is cut off before calling strftime, so the result doesn't depend on how SQLite rounds it.

Any other operand (e.g. the result of another date/time function, which is already limited to milliseconds) is evaluated once, and the Julian day is rounded to whole milliseconds while it's still exactly representable as a double:

(CAST(round(julianday(x) * 86400000.0) AS INTEGER) - 148731163200000) * 10000

The exact translation is only used when the operand is a column mapped with SqliteDateTimeTypeMapping and no value converter, since it references the operand twice and relies on the text format.

Tests

• Updated the baseline for NorthwindSelectQuerySqliteTest.Select_datetime_Ticks_component.

• Added Ticks, Ticks_projection and Ticks_on_computed_value to DateTimeTranslationsSqliteTest, covering a sub-millisecond match on a column, all seeded values against the client result, and the non-column translation.

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[Copilot]

🟡 Changes recommended

A critical active finding shows the new translation breaks DateTime properties mapped to REAL columns by applying text operations to numeric Julian-day values, so the change requires correction and a regression test.

1 open issue

• Exclude REAL-backed DateTime mappings from the text-format path · New

What changed in this PR

This pull request fixes SQLite DateTime.Ticks translation by preserving sub-millisecond precision for compatible text-backed columns and avoiding floating-point precision loss.

Changes:

• Uses integer arithmetic and direct fractional-text extraction for eligible DateTime columns.
• Uses rounded millisecond Julian-day arithmetic for computed or unsupported operands.
• Adds SQLite regression tests and updates the Northwind SQL baseline.
• Requires restricting the text-based translation to non-REAL mappings, correcting the fractional tick test value, and covering both synchronous and asynchronous execution.

File	Description
test/​EFCore.Sqlite.FunctionalTests/​Query/​Translations/​Temporal/​DateTimeTranslationsSqliteTest.cs	Adds regression tests for column, projection, and computed-value DateTime.Ticks translations.
test/​EFCore.Sqlite.FunctionalTests/​Query/​NorthwindSelectQuerySqliteTest.cs	Updates the expected SQLite SQL baseline for the Northwind DateTime.Ticks projection.
src/​EFCore.Sqlite.Core/​Query/​Internal/​Translators/​SqliteDateTimeMemberTranslator.cs	Implements precise text-based tick translation for eligible columns and millisecond-rounded fallback translation for other date/time expressions.

_{Review effort: Lite}