แก้ไข

แชร์ผ่าน


time (Transact-SQL)

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric

Defines a time of a day. The time is without time zone awareness and is based on a 24-hour clock.

Note

Informatica information is provided for PDW customers using the Informatica Connector.

time Description

Property Value
Syntax time [ (fractional second scale) ]
Usage DECLARE @MyTime time(7)

CREATE TABLE Table1 ( Column1 time(7) )
fractional seconds scale Specifies the number of digits for the fractional part of the seconds.

This can be an integer from 0 to 7. For Informatica, this can be an integer from 0 to 3.

The default fractional scale is 7 (100ns).

In Microsoft Fabric, this can be an integer from 0 to 6, with no default. Precision must be specified in Microsoft Fabric.
Default string literal format

(used for down-level client)
hh:mm:ss[.nnnnnnn] for Informatica)

For more information, see the Backward Compatibility for Down-level Clients section.
Range 00:00:00.0000000 through 23:59:59.9999999 (00:00:00.000 through 23:59:59.999 for Informatica)
Element ranges hh is two digits, ranging from 0 to 23, that represent the hour.

mm is two digits, ranging from 0 to 59, that represent the minute.

ss is two digits, ranging from 0 to 59, that represent the second.

n* is zero to seven digits, ranging from 0 to 9999999, that represent the fractional seconds. For Informatica, n* is zero to three digits, ranging from 0 to 999.
Character length 8 positions minimum (hh:mm:ss) to 16 maximum (hh:mm:ss.nnnnnnn). For Informatica, the maximum is 12 (hh:mm:ss.nnn).
Precision, scale

(user specifies scale only)
See the table below.
Storage size 5 bytes, fixed, is the default with the default of 100ns fractional second precision. In Informatica, the default is 4 bytes, fixed, with the default of 1ms fractional second precision.
Accuracy 100 nanoseconds (1 millisecond in Informatica)
Default value 00:00:00

This value is used for the appended time part for implicit conversion from date to datetime2 or datetimeoffset.
User-defined fractional second precision Yes
Time zone offset aware and preservation No
Daylight saving aware No
Specified scale Result (precision, scale) Column length (bytes) Fractional

seconds

precision
time (16,7) [(12,3) in Informatica] 5 (4 in Informatica) 7 (3 in Informatica)
time(0) (8,0) 3 0-2
time(1) (10,1) 3 0-2
time(2) (11,2) 3 0-2
time(3) (12,3) 4 3-4
time(4)* (13,4) 4 3-4
time(5)* (14,5) 5 5-7
time(6)* (15,6) 5 5-7
time(7)* + (16,7) 5 5-7

* Not supported in Informatica.

+ Not supported in Microsoft Fabric.

Supported String Literal Formats for time

The following table shows the valid string literal formats for the time data type.

SQL Server Description
hh:mm[:ss][:fractional seconds][AM][PM]

hh:mm[:ss][.fractional seconds][AM][PM]

hhAM[PM]

hh AM[PM]
The hour value of 0 represents the hour after midnight (AM), regardless of whether AM is specified. PM cannot be specified when the hour equals 0.

Hour values from 01 through 11 represent the hours before noon if neither AM nor PM is specified. The values represent the hours before noon when AM is specified. The values represent hours after noon if PM is specified.

The hour value 12 represents the hour that starts at noon if neither AM nor PM is specified. If AM is specified, the value represents the hour that starts at midnight. If PM is specified, the value represents the hour that starts at noon. For example, 12:01 is 1 minute after noon, as is 12:01 PM; and 12:01 AM is one minute after midnight. Specifying 12:01 AM is the same as specifying 00:01 or 00:01 AM.

Hour values from 13 through 23 represent hours after noon if AM or PM is not specified. The values also represent the hours after noon when PM is specified. AM cannot be specified when the hour value is from 13 through 23.

An hour value of 24 is not valid. To represent midnight, use 12:00 AM or 00:00.

Milliseconds can be preceded by either a colon (:) or a period (.). If a colon is used, the number means thousandths-of-a-second. If a period is used, a single digit means tenths-of-a-second, two digits mean hundredths-of-a-second, and three digits mean thousandths-of-a-second. For example, 12:30:20:1 indicates 20 and one-thousandth seconds past 12:30; 12:30:20.1 indicates 20 and one-tenth seconds past 12:30.
ISO 8601 Notes
hh:mm:ss

hh:mm[:ss][.fractional seconds]
hh is two digits, ranging from 0 to 23, that represent the number of hours in the time zone offset.

mm is two digits, ranging from 0 to 59, that represent the number of additional minutes in the time zone offset.
ODBC Notes
{t 'hh:mm:ss[.fractional seconds]'} ODBC API specific.

Compliance with ANSI and ISO 8601 Standards

Using hour 24 to represent midnight and leap second over 59 as defined by ISO 8601 (5.3.2 and 5.3) are not supported to be backward compatible and consistent with the existing date and time types.

The default string literal format (used for down-level client) will align with the SQL standard form, which is defined as hh:mm:ss[.nnnnnnn]. This format resembles the ISO 8601 definition for TIME excluding fractional seconds.

Backward Compatibility for Down-level Clients

Some down-level clients do not support the time, date, datetime2 and datetimeoffset data types. The following table shows the type mapping between an up-level instance of SQL Server and down-level clients.

SQL Server data type Default string literal format passed to down-level client Down-level ODBC Down-level OLEDB Down-level JDBC Down-level SQLCLIENT
time hh:mm:ss[.nnnnnnn] SQL_WVARCHAR or SQL_VARCHAR DBTYPE_WSTRor DBTYPE_STR Java.sql.String String or SqString
date YYYY-MM-DD SQL_WVARCHAR or SQL_VARCHAR DBTYPE_WSTRor DBTYPE_STR Java.sql.String String or SqString
datetime2 YYYY-MM-DD hh:mm:ss[.nnnnnnn] SQL_WVARCHAR or SQL_VARCHAR DBTYPE_WSTRor DBTYPE_STR Java.sql.String String or SqString
datetimeoffset YYYY-MM-DD hh:mm:ss[.nnnnnnn] [+|-]hh:mm SQL_WVARCHAR or SQL_VARCHAR DBTYPE_WSTRor DBTYPE_STR Java.sql.String String or SqString

Converting Date and Time Data

When you convert to date and time data types, SQL Server rejects all values it cannot recognize as dates or times. For information about using the CAST and CONVERT functions with date and time data, see CAST and CONVERT (Transact-SQL)

Converting time(n) Data Type to Other Date and Time Types

This section describes what occurs when a time data type is converted to other date and time data types.

When the conversion is to time(n), the hour, minute, and seconds are copied. When the destination precision is less than the source precision, the fractional seconds is rounded up to fit the destination precision. The following example shows the results of converting a time(4) value to a time(3) value.

DECLARE @timeFrom TIME(4) = '12:34:54.1237';
DECLARE @timeTo TIME(3) = @timeFrom;

SELECT @timeTo AS 'time(3)', @timeFrom AS 'time(4)';

Here's the result set.

time(3)      time(4)  
------------ -------------  
12:34:54.124 12:34:54.1237  

If the conversion is to date, the conversion fails, and error message 206 is raised: "Operand type clash: date is incompatible with time".

When the conversion is to datetime, hour, minute, and second values are copied; and the date component is set to '1900-01-01'. When the fractional seconds precision of the time(n) value is greater than three digits, the datetime result will be truncated. The following code shows the results of converting a time(4) value to a datetime value.

DECLARE @time TIME(4) = '12:15:04.1237';
DECLARE @datetime DATETIME = @time;

SELECT @time AS '@time', @datetime AS '@datetime';

Here's the result set.

@time         @datetime  
------------- -----------------------  
12:15:04.1237 1900-01-01 12:15:04.123  

When the conversion is to smalldatetime, the date is set to '1900-01-01', and the hour and minute values are rounded up. The seconds and fractional seconds are set to 0. The following code shows the results of converting a time(4) value to a smalldatetime value.

Show rounding up of the minute value:

DECLARE @time TIME(4) = '12:15:59.9999';
DECLARE @smalldatetime SMALLDATETIME = @time;

SELECT @time AS '@time', @smalldatetime AS '@smalldatetime';

Here's the result set.

@time            @smalldatetime  
---------------- -----------------------  
12:15:59.9999    1900-01-01 12:16:00--  

Show rounding up of the hour value:

DECLARE @time TIME(4) = '12:59:59.9999';
DECLARE @smalldatetime SMALLDATETIME = @time;

SELECT @time AS '@time', @smalldatetime AS '@smalldatetime';

Here's the result set.

@time            @smalldatetime  
---------------- -----------------------  
12:59:59.9999    1900-01-01 13:00:00  

If the conversion is to datetimeoffset(n), the date is set to '1900-01-01', and the time is copied. The time zone offset is set to +00:00. When the fractional seconds precision of the time(n) value is greater than the precision of the datetimeoffset(n) value, the value is rounded up to fit. The following example shows the results of converting a time(4) value to a datetimeoffset(3) type.

DECLARE @time TIME(4) = '12:15:04.1237';
DECLARE @datetimeoffset DATETIMEOFFSET(3) = @time;

SELECT @time AS '@time', @datetimeoffset AS '@datetimeoffset';

Here's the result set.

@time         @datetimeoffset  
------------- ------------------------------  
12:15:04.1237 1900-01-01 12:15:04.124 +00:00  

When converting to datetime2(n), the date is set to '1900-01-01', the time component is copied, and the time zone offset is set to 00:00. When the fractional seconds precision of the datetime2(n) value is greater than the time(n) value, the value will be rounded up to fit. The following example shows the results of converting a time(4) value to a datetime2(2) value.

DECLARE @time TIME(4) = '12:15:04.1237';
DECLARE @datetime2 DATETIME2(3) = @time;

SELECT @datetime2 AS '@datetime2', @time AS '@time';

Here's the result set.

@datetime2              @time  
----------------------- -------------  
1900-01-01 12:15:04.124 12:15:04.1237  

Converting String Literals to time(n)

Conversions from string literals to date and time types are permitted if all parts of the strings are in valid formats. Otherwise, a runtime error is raised. Implicit conversions or explicit conversions that do not specify a style, from date and time types to string literals will be in the default format of the current session. The following table shows the rules for converting a string literal to the time data type.

Input string literal Conversion Rule
ODBC DATE ODBC string literals are mapped to the datetime data type. Any assignment operation from ODBC DATETIME literals into timetypes will cause an implicit conversion between datetime and this type as defined by the conversion rules.
ODBC TIME See ODBC DATE rule above.
ODBC DATETIME See ODBC DATE rule above.
DATE only Default values are supplied.
TIME only Trivial
TIMEZONE only Default values are supplied.
DATE + TIME The TIME part of the input string is used.
DATE + TIMEZONE Not allowed.
TIME + TIMEZONE The TIME part of the input string is used.
DATE + TIME + TIMEZONE The TIME part of local DATETIME will be used.

Examples

A. Comparing date and time Data Types

The following example compares the results of casting a string to each date and time data type.

SELECT CAST('2007-05-08 12:35:29. 1234567 +12:15' AS TIME(7)) AS 'time',
    CAST('2007-05-08 12:35:29. 1234567 +12:15' AS DATE) AS 'date',
    CAST('2007-05-08 12:35:29.123' AS SMALLDATETIME) AS 'smalldatetime',
    CAST('2007-05-08 12:35:29.123' AS DATETIME) AS 'datetime',
    CAST('2007-05-08 12:35:29. 1234567 +12:15' AS DATETIME2(7)) AS 'datetime2',
    CAST('2007-05-08 12:35:29.1234567 +12:15' AS DATETIMEOFFSET(7)) AS 'datetimeoffset';
Data type Output
time 12:35:29. 1234567
date 2007-05-08
smalldatetime 2007-05-08 12:35:00
datetime 2007-05-08 12:35:29.123
datetime2 2007-05-08 12:35:29. 1234567
datetimeoffset 2007-05-08 12:35:29.1234567 +12:15

B. Inserting Valid Time String Literals into a time(7) Column

The following table lists different string literals that can be inserted into a column of data type time(7) with the values that are then stored in that column.

String literal format type Inserted string literal time(7) value that is stored Description
SQL Server '01:01:01:123AM' 01:01:01.1230000 When a colon (:) comes before fractional seconds precision, scale cannot exceed three positions or an error will be raised.
SQL Server '01:01:01.1234567 AM' 01:01:01.1234567 When AM or PM is specified, the time is stored in 24-hour format without the literal AM or PM
SQL Server '01:01:01.1234567 PM' 13:01:01.1234567 When AM or PM is specified, the time is stored in 24-hour format without the literal AM or PM
SQL Server '01:01:01.1234567PM' 13:01:01.1234567 A space before AM or PM is optional.
SQL Server '01AM' 01:00:00.0000000 When only the hour is specified, all other values are 0.
SQL Server '01 AM' 01:00:00.0000000 A space before AM or PM is optional.
SQL Server '01:01:01' 01:01:01.0000000 When fractional seconds precision is not specified, each position that is defined by the data type is 0.
ISO 8601 '01:01:01.1234567' 01:01:01.1234567 To comply with ISO 8601, use 24-hour format, not AM or PM.
ISO 8601 '01:01:01.1234567 +01:01' 01:01:01.1234567 The optional time zone difference (TZD) is allowed in the input but is not stored.

C. Inserting Time String Literal into Columns of Each date and time Date Type

In the following table the first column shows a time string literal to be inserted into a database table column of the date or time data type shown in the second column. The third column shows the value that will be stored in the database table column.

Inserted string literal Column data type Value that is stored in column Description
'12:12:12.1234567' time(7) 12:12:12.1234567 If the fractional seconds precision exceeds the value specified for the column, the string will be truncated without error.
'2007-05-07' date NULL Any time value will cause the INSERT statement to fail.
'12:12:12' smalldatetime 1900-01-01 12:12:00 Any fractional seconds precision value will cause the INSERT statement to fail.
'12:12:12.123' datetime 1900-01-01 12:12:12.123 Any second precision longer than three positions will cause the INSERT statement to fail.
'12:12:12.1234567' datetime2(7) 1900-01-01 12:12:12.1234567 If the fractional seconds precision exceeds the value specified for the column, the string will be truncated without error.
'12:12:12.1234567' datetimeoffset(7) 1900-01-01 12:12:12.1234567 +00:00 If the fractional seconds precision exceeds the value specified for the column, the string will be truncated without error.

See Also

CAST and CONVERT (Transact-SQL)