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Merged
adamziel merged 10 commits into from
Mar 12, 2026
+380 −10
Merged

Accept zero dates when NO_ZERO_DATE SQL mode is off #327

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f8c58de
Accept zero dates when NO_ZERO_DATE and NO_ZERO_IN_DATE SQL modes are…
adamziel Mar 11, 2026
e962cdf
Inline zero-date mode checks into the CASE expression
adamziel Mar 11, 2026
025b03d
Fix PHPCS code style violations
adamziel Mar 11, 2026
be86458
Use strtr with named placeholders for the zero-date CASE expression
adamziel Mar 11, 2026
7763982
Fix the zero-date CASE expression to compare the function call result…
adamziel Mar 11, 2026
cc3c494
Test that UPDATE rejects zero dates in strict mode
adamziel Mar 12, 2026
13c8a34
Test zero dates in SELECT and fix YEAR/MONTH/DAY for zero dates
adamziel Mar 12, 2026
8e2c32f
Fix PHPCS: use single quotes for SQL string without interpolation
adamziel Mar 12, 2026
c199ff8
Restore PHP datetime.format.php documentation comments
adamziel Mar 12, 2026
131d3b2
Anchor date-extraction regexps with ^
adamziel Mar 12, 2026
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301 changes: 301 additions & 0 deletions tests/WP_SQLite_Driver_Tests.php
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Original file line number Diff line number Diff line change
Expand Up @@ -2370,6 +2370,307 @@ public function testTruncatesInvalidDates() {
$this->assertEquals( '0000-00-00 00:00:00', $results[1]->option_value );
}

/**
* Test NO_ZERO_DATE SQL mode behavior.
*
* MySQL reference (https://dev.mysql.com/doc/refman/8.4/en/sql-mode.html#sqlmode_no_zero_date):
*
* "The NO_ZERO_DATE mode affects whether the server permits '0000-00-00' as a valid date.
* Its effect also depends on whether strict SQL mode is enabled.
* - If this mode is not enabled, '0000-00-00' is permitted and inserts produce no warning.
* - If this mode is enabled, '0000-00-00' is permitted but produces a warning.
* - If this mode and strict mode are both enabled, '0000-00-00' is not permitted
* and inserts produce an error, unless IGNORE is also given."
*/
public function testZeroDateAcceptedWhenNoZeroDateModeIsOff() {
// With NO_ZERO_DATE disabled, '0000-00-00 00:00:00' should be accepted.
$this->assertQuery( "SET sql_mode = 'STRICT_TRANS_TABLES'" );

$this->assertQuery( "INSERT INTO _dates (option_value) VALUES ('0000-00-00 00:00:00');" );

$this->assertQuery( 'SELECT * FROM _dates;' );
$results = $this->engine->get_query_results();
$this->assertCount( 1, $results );
$this->assertEquals( '0000-00-00 00:00:00', $results[0]->option_value );
}

/**
* Test that zero dates are rejected in strict mode when NO_ZERO_DATE is active.
*
* MySQL reference (https://dev.mysql.com/doc/refman/8.4/en/sql-mode.html#sqlmode_no_zero_date):
*
* "If this mode and strict mode are both enabled, '0000-00-00' is not
* permitted and inserts produce an error."
*/
public function testZeroDateRejectedWhenNoZeroDateAndStrictModeAreOn() {
// Default modes include both NO_ZERO_DATE and STRICT_TRANS_TABLES.
$this->assertQueryError(
"INSERT INTO _dates (option_value) VALUES ('0000-00-00 00:00:00');",
"Incorrect datetime value: '0000-00-00 00:00:00'"
);
}

/**
* Test that zero dates are accepted (with warning) when NO_ZERO_DATE is on
* but strict mode is off.
*
* MySQL reference (https://dev.mysql.com/doc/refman/8.4/en/sql-mode.html#sqlmode_no_zero_date):
*
* "If this mode is enabled, '0000-00-00' is permitted but produces a warning."
*/
public function testZeroDateAcceptedWhenNoZeroDateOnButStrictModeOff() {
$this->assertQuery( "SET sql_mode = 'NO_ZERO_DATE'" );

$this->assertQuery( "INSERT INTO _dates (option_value) VALUES ('0000-00-00 00:00:00');" );

$this->assertQuery( 'SELECT * FROM _dates;' );
$results = $this->engine->get_query_results();
$this->assertCount( 1, $results );
$this->assertEquals( '0000-00-00 00:00:00', $results[0]->option_value );
}

/**
* Test that zero dates work with the DATE column type too.
*/
public function testZeroDateAcceptedForDateColumn() {
$this->assertQuery( "SET sql_mode = 'STRICT_TRANS_TABLES'" );

$this->assertQuery(
'CREATE TABLE _date_test (
ID INTEGER PRIMARY KEY AUTO_INCREMENT NOT NULL,
col_date DATE NOT NULL
);'
);

$this->assertQuery( "INSERT INTO _date_test (col_date) VALUES ('0000-00-00');" );

$this->assertQuery( 'SELECT * FROM _date_test;' );
$results = $this->engine->get_query_results();
$this->assertCount( 1, $results );
$this->assertEquals( '0000-00-00', $results[0]->col_date );
}

/**
* Test NO_ZERO_IN_DATE SQL mode behavior.
*
* MySQL reference (https://dev.mysql.com/doc/refman/8.4/en/sql-mode.html#sqlmode_no_zero_in_date):
*
* "The NO_ZERO_IN_DATE mode affects whether the server permits dates in
* which the year part is nonzero but the month or day part is 0. (This
* mode affects dates such as '2010-00-01' or '2010-01-00', but not
* '0000-00-00'. To control whether the server permits '0000-00-00',
* use the NO_ZERO_DATE mode.)
* - If this mode is not enabled, dates with zero parts are permitted
* and inserts produce no warning.
* - If this mode is enabled, dates with zero parts are inserted as
* '0000-00-00' and produce a warning.
* - If this mode and strict mode are both enabled, dates with zero parts
* are not permitted and inserts produce an error."
*/
public function testZeroInDateAcceptedWhenNoZeroInDateModeIsOff() {
// Disable NO_ZERO_IN_DATE but keep strict mode on.
$this->assertQuery( "SET sql_mode = 'STRICT_TRANS_TABLES'" );

$this->assertQuery( "INSERT INTO _dates (option_value) VALUES ('2020-00-15 00:00:00');" );
$this->assertQuery( "INSERT INTO _dates (option_value) VALUES ('2020-01-00 00:00:00');" );
$this->assertQuery( "INSERT INTO _dates (option_value) VALUES ('2020-00-00 00:00:00');" );

$this->assertQuery( 'SELECT * FROM _dates;' );
$results = $this->engine->get_query_results();
$this->assertCount( 3, $results );
$this->assertEquals( '2020-00-15 00:00:00', $results[0]->option_value );
$this->assertEquals( '2020-01-00 00:00:00', $results[1]->option_value );
$this->assertEquals( '2020-00-00 00:00:00', $results[2]->option_value );
}

/**
* Test that dates with zero parts are rejected in strict mode when
* NO_ZERO_IN_DATE is active.
*/
public function testZeroInDateRejectedWhenNoZeroInDateAndStrictModeAreOn() {
// Default modes include both NO_ZERO_IN_DATE and STRICT_TRANS_TABLES.
$this->assertQueryError(
"INSERT INTO _dates (option_value) VALUES ('2020-00-15 00:00:00');",
"Incorrect datetime value: '2020-00-15 00:00:00'"
);
}

/**
* Test that dates with zero parts get stored as '0000-00-00 00:00:00'
* when NO_ZERO_IN_DATE is on but strict mode is off.
*
* MySQL reference (https://dev.mysql.com/doc/refman/8.4/en/sql-mode.html#sqlmode_no_zero_in_date):
*
* "If this mode is enabled, dates with zero parts are inserted as
* '0000-00-00' and produce a warning."
*/
public function testZeroInDateBecomesZeroDateWhenNoZeroInDateOnButStrictOff() {
$this->assertQuery( "SET sql_mode = 'NO_ZERO_IN_DATE'" );

$this->assertQuery( "INSERT INTO _dates (option_value) VALUES ('2020-00-15 00:00:00');" );

$this->assertQuery( 'SELECT * FROM _dates;' );
$results = $this->engine->get_query_results();
$this->assertCount( 1, $results );
$this->assertEquals( '0000-00-00 00:00:00', $results[0]->option_value );
}

/**
* Test that all modes disabled allows both zero dates and zero-in-dates.
*/
public function testBothZeroDateModesDisabledAcceptsAll() {
$this->assertQuery( "SET sql_mode = ''" );

$this->assertQuery( "INSERT INTO _dates (option_value) VALUES ('0000-00-00 00:00:00');" );
$this->assertQuery( "INSERT INTO _dates (option_value) VALUES ('2020-00-15 00:00:00');" );
$this->assertQuery( "INSERT INTO _dates (option_value) VALUES ('2020-01-00 00:00:00');" );

$this->assertQuery( 'SELECT * FROM _dates;' );
$results = $this->engine->get_query_results();
$this->assertCount( 3, $results );
$this->assertEquals( '0000-00-00 00:00:00', $results[0]->option_value );
$this->assertEquals( '2020-00-15 00:00:00', $results[1]->option_value );
$this->assertEquals( '2020-01-00 00:00:00', $results[2]->option_value );
}

/**
* Test that valid dates still work correctly regardless of zero date modes.
*/
public function testValidDatesWorkWithZeroDateModes() {
// Default modes (NO_ZERO_DATE + STRICT_TRANS_TABLES).
$this->assertQuery( "INSERT INTO _dates (option_value) VALUES ('2022-01-15 14:30:00');" );

$this->assertQuery( 'SELECT * FROM _dates;' );
$results = $this->engine->get_query_results();
$this->assertCount( 1, $results );
$this->assertEquals( '2022-01-15 14:30:00', $results[0]->option_value );
}

/**
* Test zero date handling in UPDATE statements.
*/
public function testZeroDateInUpdate() {
$this->assertQuery( "SET sql_mode = 'STRICT_TRANS_TABLES'" );

$this->assertQuery( "INSERT INTO _dates (option_value) VALUES ('2022-01-15 14:30:00');" );
$this->assertQuery( "UPDATE _dates SET option_value = '0000-00-00 00:00:00';" );

$this->assertQuery( 'SELECT * FROM _dates;' );
$results = $this->engine->get_query_results();
$this->assertCount( 1, $results );
$this->assertEquals( '0000-00-00 00:00:00', $results[0]->option_value );
}

/**
* Test that zero dates are rejected in UPDATE when NO_ZERO_DATE and strict mode are on.
*/
public function testZeroDateInUpdateRejectedWhenNoZeroDateAndStrictModeAreOn() {
// Default modes include both NO_ZERO_DATE and STRICT_TRANS_TABLES.
$this->assertQuery( "INSERT INTO _dates (option_value) VALUES ('2022-01-15 14:30:00');" );
$this->assertQueryError(
"UPDATE _dates SET option_value = '0000-00-00 00:00:00';",
"Incorrect datetime value: '0000-00-00 00:00:00'"
);
}

/**
* Test that dates with zero parts are rejected in UPDATE when
* NO_ZERO_IN_DATE and strict mode are on.
*/
public function testZeroInDateInUpdateRejectedWhenNoZeroInDateAndStrictModeAreOn() {
// Default modes include both NO_ZERO_IN_DATE and STRICT_TRANS_TABLES.
$this->assertQuery( "INSERT INTO _dates (option_value) VALUES ('2022-01-15 14:30:00');" );
$this->assertQueryError(
"UPDATE _dates SET option_value = '2020-00-15 00:00:00';",
"Incorrect datetime value: '2020-00-15 00:00:00'"
);
}

/**
* Test that stored zero dates can be selected and compared.
*
* In MySQL, zero dates are regular values for reads — they can appear in
* WHERE, ORDER BY, and comparisons regardless of the current SQL mode.
*/
public function testSelectZeroDatesComparison() {
$this->assertQuery( "SET sql_mode = 'STRICT_TRANS_TABLES'" );

$this->assertQuery( "INSERT INTO _dates (option_name, option_value) VALUES ('zero', '0000-00-00 00:00:00');" );
$this->assertQuery( "INSERT INTO _dates (option_name, option_value) VALUES ('real', '2022-01-15 14:30:00');" );

// Zero dates compare as less than real dates.
$this->assertQuery( "SELECT option_name FROM _dates WHERE option_value < '2000-01-01 00:00:00' ORDER BY option_value;" );
$results = $this->engine->get_query_results();
$this->assertCount( 1, $results );
$this->assertEquals( 'zero', $results[0]->option_name );

// Equality match on zero date.
$this->assertQuery( "SELECT option_name FROM _dates WHERE option_value = '0000-00-00 00:00:00';" );
$results = $this->engine->get_query_results();
$this->assertCount( 1, $results );
$this->assertEquals( 'zero', $results[0]->option_name );
}

/**
* Test ORDER BY with a mix of zero and non-zero dates.
*/
public function testSelectZeroDatesOrderBy() {
$this->assertQuery( "SET sql_mode = 'STRICT_TRANS_TABLES'" );

$this->assertQuery( "INSERT INTO _dates (option_name, option_value) VALUES ('b', '2022-06-01 00:00:00');" );
$this->assertQuery( "INSERT INTO _dates (option_name, option_value) VALUES ('a', '0000-00-00 00:00:00');" );
$this->assertQuery( "INSERT INTO _dates (option_name, option_value) VALUES ('c', '2023-01-01 00:00:00');" );

$this->assertQuery( 'SELECT option_name FROM _dates ORDER BY option_value ASC;' );
$results = $this->engine->get_query_results();
$this->assertCount( 3, $results );
$this->assertEquals( 'a', $results[0]->option_name );
$this->assertEquals( 'b', $results[1]->option_name );
$this->assertEquals( 'c', $results[2]->option_name );
}

/**
* Test that zero-in-dates stored in the database can be read back
* and filtered in SELECT statements.
*/
public function testSelectZeroInDates() {
$this->assertQuery( "SET sql_mode = 'STRICT_TRANS_TABLES'" );

$this->assertQuery( "INSERT INTO _dates (option_name, option_value) VALUES ('zero-month', '2020-00-15 00:00:00');" );
$this->assertQuery( "INSERT INTO _dates (option_name, option_value) VALUES ('zero-day', '2020-01-00 00:00:00');" );
$this->assertQuery( "INSERT INTO _dates (option_name, option_value) VALUES ('normal', '2020-01-15 00:00:00');" );

// All three rows are readable.
$this->assertQuery( 'SELECT option_name, option_value FROM _dates ORDER BY option_value ASC;' );
$results = $this->engine->get_query_results();
$this->assertCount( 3, $results );
$this->assertEquals( '2020-00-15 00:00:00', $results[0]->option_value );
$this->assertEquals( '2020-01-00 00:00:00', $results[1]->option_value );
$this->assertEquals( '2020-01-15 00:00:00', $results[2]->option_value );

// Filtering by a zero-in-date value works.
$this->assertQuery( "SELECT option_name FROM _dates WHERE option_value = '2020-00-15 00:00:00';" );
$results = $this->engine->get_query_results();
$this->assertCount( 1, $results );
$this->assertEquals( 'zero-month', $results[0]->option_name );
}

/**
* Test date functions on zero dates — YEAR(), MONTH(), DAY() all return 0.
*/
public function testDateFunctionsOnZeroDates() {
$this->assertQuery( "SET sql_mode = 'STRICT_TRANS_TABLES'" );

$this->assertQuery( "INSERT INTO _dates (option_name, option_value) VALUES ('zero', '0000-00-00 00:00:00');" );

$this->assertQuery( 'SELECT YEAR(option_value) as y, MONTH(option_value) as m, DAY(option_value) as d FROM _dates;' );
$results = $this->engine->get_query_results();
$this->assertCount( 1, $results );
$this->assertEquals( 0, $results[0]->y );
$this->assertEquals( 0, $results[0]->m );
$this->assertEquals( 0, $results[0]->d );
}

public function testCaseInsensitiveSelect() {
$this->assertQuery(
"CREATE TABLE _tmp_table (
Expand Down
66 changes: 56 additions & 10 deletions wp-includes/sqlite-ast/class-wp-pdo-mysql-on-sqlite.php
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -4494,14 +4494,30 @@ private function translate_datetime_literal( string $value ): string {
* In the future, let's update WordPress to do its own date validation
* and stop relying on this MySQL feature,
*/
if ( 1 === preg_match( '/^(\d{4}-\d{2}-\d{2}) (\d{2}:\d{2}:\d{2})$/', $value, $matches ) ) {
if ( 1 === preg_match( '/^(\d{4})-(\d{2})-(\d{2}) (\d{2}:\d{2}:\d{2})$/', $value, $matches ) ) {
/*
* Calling strtotime("0000-00-00 00:00:00") in 32-bit environments triggers
* an "out of integer range" warning – let's avoid that call for the popular
* case of "zero" dates.
*/
if ( '0000-00-00 00:00:00' !== $value && false === strtotime( $value ) ) {
$value = '0000-00-00 00:00:00';
/*
* Check for dates with zero month/day parts (e.g. '2020-00-15 00:00:00').
*
* When the NO_ZERO_IN_DATE SQL mode is not active, MySQL accepts dates
* where the year is nonzero but the month or day is zero. We must
* preserve these values so that cast_value_for_saving() can handle
* them correctly at the column level.
*
* See: https://dev.mysql.com/doc/refman/8.4/en/sql-mode.html#sqlmode_no_zero_in_date
*/
$has_zero_in_date = (
( '00' === $matches[2] || '00' === $matches[3] ) &&
'0000' !== $matches[1]
);
if ( ! $has_zero_in_date || $this->is_sql_mode_active( 'NO_ZERO_IN_DATE' ) ) {
$value = '0000-00-00 00:00:00';
}
}
}
return $value;
Expand Down Expand Up @@ -5660,16 +5676,46 @@ private function cast_value_for_saving(
? 'NULL'
: $this->quote_sqlite_value( $implicit_default );
}
return sprintf(

/*
* Build the CASE expression for date/time validation.
*
* SQLite's DATE()/DATETIME() functions return NULL for zero
* dates, so the CASE includes explicit checks controlled by
* the NO_ZERO_DATE and NO_ZERO_IN_DATE SQL modes.
*
* In MySQL, the behavior of zero dates depends on these modes:
*
* NO_ZERO_DATE (see https://dev.mysql.com/doc/refman/8.4/en/sql-mode.html#sqlmode_no_zero_date):
* - Disabled: '0000-00-00' is permitted and produces no warning.
* - Enabled without strict mode: '0000-00-00' is permitted but produces a warning.
* - Enabled with strict mode: '0000-00-00' is not permitted and produces an error.
*
* NO_ZERO_IN_DATE (see https://dev.mysql.com/doc/refman/8.4/en/sql-mode.html#sqlmode_no_zero_in_date):
* - Disabled: dates with zero month/day parts (e.g. '2020-00-15') are permitted.
* - Enabled without strict mode: zero-part dates produce a warning and are stored as '0000-00-00'.
* - Enabled with strict mode: zero-part dates produce an error.
*/
return strtr(
"CASE
WHEN %s IS NULL THEN NULL
WHEN %s > '0' THEN %s
ELSE %s
WHEN {value} IS NULL THEN NULL
WHEN {value} IN ('0000-00-00', '0000-00-00 00:00:00') AND NOT {reject_zero_date} THEN {zero_date_value}
WHEN SUBSTR({value}, 1, 4) != '0000' AND (SUBSTR({value}, 6, 2) = '00' OR SUBSTR({value}, 9, 2) = '00') AND NOT {reject_zero_in_date} THEN {value}
WHEN {function_call} > '0' THEN {function_call}
ELSE {fallback}
END",
$translated_value,
$function_call,
$function_call,
$fallback
array(
'{value}' => $translated_value,
'{reject_zero_date}' => (
$this->is_sql_mode_active( 'NO_ZERO_DATE' ) && $is_strict_mode
) ? 1 : 0,
'{zero_date_value}' => 'date' === $mysql_data_type
? "'0000-00-00'"
: "'0000-00-00 00:00:00'",
'{reject_zero_in_date}' => $this->is_sql_mode_active( 'NO_ZERO_IN_DATE' ) ? 1 : 0,
'{function_call}' => $function_call,
'{fallback}' => $fallback,
)
);
default:
/*
Expand Down
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