Get numeric value from string using TSQL

Introduction
Many times while working on applications, we often land into a situation where we want to get the only numeric values from alpha numeric string. There are some approaches given, like you may achieve it with making a loop and without loop.


Approaches
I have prescribed as a simple query, but you will achieve same by making a function.

1. Get the numbers through loop.

DECLARE @AlphaNumericString VARCHAR(MAX) = 'ABC1DEF2GHI3'

DECLARE @NumericValueIndex INT

SET @NumericValueIndex = PATINDEX('%[^0-9]%', @AlphaNumericString)

WHILE @NumericValueIndex > 0

BEGIN

SET @AlphaNumericString = STUFF(@AlphaNumericString, @NumericValueIndex, 1, '' )

SET @NumericValueIndex = PATINDEX('%[^0-9]%', @AlphaNumericString )

END

SELECT ISNULL(@AlphaNumericString,0) 'Numeric Values'

OUTPUT

2. Get the numbers without loop.

DECLARE @AlphaNumericString VARCHAR(MAX) = 'ABC1DEF2GHI3'

DECLARE @NumericValues VARCHAR(MAX) = ''

SELECT

@NumericValues =

@NumericValues +

CASE WHEN NumericValue like '[0-9]' THEN NumericValue ELSE '' END FROM

(

SELECT

SUBSTRING(@AlphaNumericString,NumericValue,1) NumericValue

FROM

(

SELECT

number NumericValue

FROM

master..spt_values

WHERE 

TYPE = 'p' 

AND number BETWEEN 1 AND LEN(@AlphaNumericString)

) T

) T

SELECT ISNULL(@NumericValues,0) 'Numeric Values'

OUTPUT

Limitation
There is a limitation in 2nd approach, the table “master..spt_values” contains only 2048 rows value. So if you want to get the numbers from the very big text contains above 2048 characters, then this approach is not suitable.
To over come this limitation, you can use “Tally Table” instead of “master..spt_values”. Replace “master..spt_values” with “Tally Table”.
Want to get more information about Tally Table? Click here.


Conclusion
If you have the need of numeric values only from less characters of 2048, then no need to process for “Tally Table”. Just use the “master..spt_values”.

New Date and Time Functions in SQL Server 2008

Introduction

SQL Server 2008 introduces five new date and time functions namely SYSDATETIME, SYSDATETIMEOFFSET, SYSUTCDATETIME, SWITCHOFFSET and TODATETIMEOFFSET.

In this article described new functions in detail.

1)   SYSDATETIME

The SYSDATETIME function basically returns the current system timestamp without the time zone information.

SELECT SYSDATETIME()

GO

SYSDATETIME

------------------------

2011-06-27 16:06:15.9409129

2)   SYSDATETIMEOFFSET

The SYSDATETIMEOFFSET function is much similar to SYSDATETIME function; however it will also get you the time zone information.

SELECT SYSDATETIMEOFFSET()

GO

SYSDATETIMEOFFSET

-------------------------------

2011-06-27 16:07:01.8205935 +05:30

3)   SYSUTCDATETIME

The SYSUTCDATETIME function returns the Greenwich Mean Time (GMT) or the Coordinated Universal Time (UTC). This time is derived from the current local system time and the time zone settings of the server where SQL Server 2008 is running.

SELECT SYSUTCDATETIME()

GO

SYSUTCDATETIME

------------------------

2011-06-27 10:38:25.6239407

4)   SWITCHOFFSET

The SWITCHOFFSET function returns a DATETIMEOFFSET value that is changed from the stored time zone offset to a specified new time zone offset.

SELECT SYSDATETIMEOFFSET(),

       SWITCHOFFSET (SYSDATETIMEOFFSET(), '+00:00')

GO

SYSDATETIMEOFFSET                                            SWITCHOFFSET

-------------------------------                                        -------------------------------------

2011-06-27 16:30:55.7127120 +05:30           2011-06-27 11:00:55.7127120 +00:00

5)   TODATETIMEOFFSET

The TODATETIMEOFFSET function returns a DATETIMEOFFSET value that is translated from a DATETIME2 expression.

SELECT TODATETIMEOFFSET (GETDATE(),'+05:30')

GO

TODATETIMEOFFSET

---------------------------------

2011-06-27 16:26:56.340 +05:30

Truncate decimals instead of Rounding from a double value In C#

Introduction

Many times while working on applications, we often land into a situation where we want to truncate the decimal places from a number instead of round like suppose we have 5.329 and I want to truncate the third digit then my required output will be 5.32. Here, I will walk through the different ways which I know in which we can achieve the same.

Approaches

I have created the approaches as making the C# method.

1.      Truncate the decimals through the string operations.

Below method only usable if you want to truncate the decimal places to two.

#region Round

/// <summary>

/// Truncate the last digit after two digit floating points.

/// </summary>

/// <param name="value">A double-precision floating-point number to be rounded.</param>

/// <returns>Double value contains two digit floating points.</returns>

public static double Round (double value)

{

  double returnValue = 0;

  try

  {

    //Convert the value into the string for round.

    string input = Convert.ToString(value);

    //Check if the input contains decimal places

    if (input.Contains("."))

    {

      //Check if there are 3 or more digits after the decimal point.

      if (input.Length - input.IndexOf(".", StringComparison.Ordinal) >= 4)

      {

        //Replace the input value with the required value.

        //Added 3 to get only 2 digits after the decimal point.

        input = input.Substring(0, input.IndexOf(".", StringComparison.Ordinal) + 3);

      }

    }

        //Converts the string representation of a number to its System.Double equivalent.

    returnValue = Convert.ToDouble(input);

  }

  catch { } //Suppress exception no need to handle.

  return returnValue;

}

#endregion

2.      Truncate the decimals through the mathematical operations.

Through this method you can truncate any number of decimal places.

#region Round

/// <summary>

/// Rounds a decimal value to a specified number of fractional digits.

/// </summary>

/// <param name="value">A decimal number to be rounded.</param>

/// <param name="decimals">The number of decimal places in the return value.</param>

/// <returns>The number nearest to value that contains a number of fractional digits equal to decimals.</returns>

public static double Round(double value, byte decimals)

{

  double returnValue = 0;

  try

  {

    if (value != 0)

    {

      //Gets the power of 10 base on passed decimal parameter value (10^decimals).

      double powValue = Math.Pow(10, decimals);

      //Gets the truncated value.

      returnValue = Math.Truncate(CDCommon.ToDouble(value * powValue)) / powValue;

    }

  }

  catch

  { throw; }

  return returnValue;

}

#endregion

Conclusion

From both the ways, as per my opinion prefer the second approach in implementation because it’s very light compared to the first in terms of calculations.

New DATETIME Data Types in SQL Server 2008

Introduction

From the beginning, Microsoft SQL Server DBAs have longed for two different data types, where you could store time and date separately. The long wait is over. In all of the older versions, we had only one data type that could store Datetime data type, and it stored both the value of the date and the value of the time.
Finally, in Microsoft SQL Server 2008, Microsoft is introducing a set of new data types for storing date, time and both date and time together. The new data types store more data as well, which means you can store dates anywhere from 01-01-01 to 9999-12-31 and also store time up to the fraction of 9999999.
There are four DATETIME data types newly introduced in SQL Server 2008. They are
DATE, TIME, DATETIMEOFFSET and DATETIME2.

1) DATE Data Type

The DATE data type stores only the date value.

The DATE data type returns data in the form of year, Month and Day. However, the format in which the date is returned is determined by the current language setting in SQL Server.

The range for the DATE data type is from 0001-01-01 through 9999-12-31.

When you specify a datetime value, SQL Server automatically converts that value into the DATE data type, which means that only the date portion is stored.

Example:

DECLARE @Date_Type DATE

SET @Date_Type = '2011-05-17 05:29:15.1234567'

SELECT @Date_Type

Result:

  2011-05-17

2) TIME Data type

The TIME data type stores only the time value. 

The TIME data type returns data in the form of hour, minute, second and fractional second.

The fractional part of the seconds can support up to 7 decimal places.

The precision of the TIME data type supports a range of 00:00:00.0000000 through 23:59:59.9999999.

When you specify the TIME datatype in a Transact-SQL statement, you can specify the precision of the stored values by including the appropriate number within parentheses.

For example, to specify a precision of 7, you would specify TIME(7).

For a precision of 5, you would specify TIME(5), and so on.

If you do not specify the precision, 7 are assumed.

Example:

DECLARE @Time_Type TIME

SET @Time_Type = '2011-05-17 05:29:15.1234567'

SELECT @Time_Type

Result:

  05:29:15.1234567

You can also specify a different precision when converting the data

DECLARE @DateTimeOffset_Type TIME

DECLARE @Time_Type TIME

SET @DateTimeOffset_Type = '2011-05-17 05:29:15.1234567'

SET @Time_Type = CAST(@DateTimeOffset_Type AS TIME(5))

SELECT @Time_Type

Result:

  05:29:15.1234600

Notice that the fractional seconds have been rounded up.

The original fractional seconds were .1234567. However, if you specify a precision of 5, SQL Server will round up the "67" fractional part, returning .1234600 in the results, rather than .1234500.

When inserting data into a TIME column, you can specify a time value or a datetime value as shown in the following INSERT statements:

INSERT INTO TableName (ID, Time_DataType)

VALUES ('1004, 05:23:10.1234567');    --Only Time

INSERT INTO TableName (ID, Time_DataType)

VALUES (1005, '2011-05-17 05:23:10.1234567');  --Date & Time

In both cases, only the time is inserted into the Time_DataType column.

3) DATETIME2 Data Type

The DATETIME2 data type stores the both date and time value.

The data type DATETIME2 is the combination of the data type DATE and TIME.

DATETIME2 is used to store both a date value ranging from 01-01-01 to 9999-12-31 as well as a time value 00:00:00.0000000 to 23:59:59.9999999.

Example:

DECLARE @DateTime2_Type DATETIME2

SET @DateTime2_Type = CONVERT(DATETIME2,'01/01/0001 16:14:00.1234567')

SELECT @DateTime2_Type

Result:

  0001-01-01 16:14:00.1234567 

We could limit the precision like (Precision value range 0-7),

DECLARE @DateTime2_Type DATETIME2(4)

SET @DateTime2_Type = CONVERT(DATETIME2,'01/01/0001 16:14:00.1234567')

SELECT @DateTime2_Type

Result:

  0001-01-01 16:14:00.1235

Notice that the fractional seconds have been rounded up.

4) DATETIMEOFFSET Data type

The DATETIMEOFFSET data type stores the date, time and time-zone offset value.

The DATETIMEOFFSET data type is nearly identical to the DATETIME2 data type, except that a DATETIMEOFFSET value includes one important addition that is a time-zone offset value.

The offset value represents the number of hours and minutes before or after Coordinated Universal Time (UTC).

A positive number indicates the amount of time to add to the UTC to determine the local time. (+05:30).

A negative number indicates the amount of time to subtract from the UTC to determine the local time. (-05:30)

The Date range is between 0001-01-01 and 9999-12-31.

The Time Range is between 00:00:00 and 23:59:59.9999999.

The Offset range is between -14:00 through +14:00.

Example:

DECLARE @DateTimeOffset_Type DATETIMEOFFSET

SET @DateTimeOffset_Type = CONVERT(DATETIMEOFFSET,'01/01/0001 16:14:00.1234567 +5:30')

SELECT @DateTimeOffset_Type

Result:

  0001-01-01 16:14:00.1234567 +05:30

You can also set the precision of the data type, like

DECLARE @DateTimeOffset_Type DATETIMEOFFSET(4)

SET @DateTimeOffset_Type = CONVERT(DATETIMEOFFSET,'01/01/0001 16:14:00.1234567 +5:30')

SELECT @DateTimeOffset_Type

Result:

  0001-01-01 16:14:00.1235 +05:30

Summary:

Data type	Format	Range	Accuracy	Storage size (bytes)	User-defined fractional second precision	Time zone offset
TIME	hh:mm:ss[.nnnnnnn]	00:00:00.0000000  to 23:59:59.9999999	100 nanoseconds	3 to 5	Yes	No
DATE	YYYY-MM-DD	00001-01-01 to 9999-12-31	1 day	3	No	No
SMALLDATETIME	YYYY-MM-DD hh:mm:ss	1900-01-01 to 2079-06-06	1 minute	4	No	No
DATETIME	YYYY-MM-DD hh:mm:ss[.nnn]	1753-01-01 to 9999-12-31	0.333 second	8	No	No
DATETIME2	YYYY-MM-DD hh:mm:ss[.nnnnnnn]	0001-01-01 00:00:00.0000000 to 9999-12-31 23:59:59.9999999	100 nanoseconds	6 to 8	Yes	No
DATETIMEOFFSET	YYYY-MM-DD hh:mm:ss[.nnnnnnn] [+|-]hh:mm	00001-01-01 00:00:00.0000000 to 9999-12-31 23:59:59.9999999 (in UTC)	100 nanoseconds	8 to 10	Yes	Yes