Project Settings (Conversion) (SybaseToSQL)

Artikkeli
02/28/2023

The Conversion page of the Project Settings dialog box contains settings that customize how SSMA converts SAP Adaptive Server Enterprise (ASE) syntax to SQL Server or Azure SQL syntax.

The Conversion pane is available in the Project Settings and Default Project Settings dialog boxes:

If you want to specify settings for all SSMA projects, on the Tools menu, select Default Project Settings, click General at the bottom of the left pane, and then click Conversion.
To specify settings for the current project, on the Tools menu, select Project Settings, click General at the bottom of the left pane, and then click Conversion.

Miscellaneous section

@@ERROR

SQL Server/Azure SQL and ASE use different error codes.

Use this setting to specify the type of message (Warning or Error) that SSMA shows in the Output or Error List pane when it encounters a reference to @@ERROR in the ASE code.

If you select Convert and mark with warning, SSMA will convert the statements and mark them with warning comments.
If you select Mark with error, SSMA will skip conversion and mark the statements with error comments.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Convert and mark with warning
Optimistic	Convert and mark with warning
Full	Mark with error

Conversion of LIKE operator

Specifies whether to convert LIKE operands to match SAP ASE behavior. The point is that ASE trims trailing blanks in a like pattern. The workaround is to make a cast of right expression to a fixed length data type with a maximum precision.

Select Simple conversion to convert the expressions without any correction.
To use the ASE behavior select Cast to fixed length.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Simple conversion
Optimistic	Simple conversion
Full	Cast to fixed length

CONVERT or CAST empty strings to numeric types

Specifies how to handle empty or blank strings within CONVERT or CAST expressions with numeric type as datatype argument. The following options are available for this setting:

Select Simple conversion to convert the expressions without any correction.
If Empty string as zero numeric is selected, then string parameter {s} will be replaced with CASE ltrim(rtrim({s})) WHEN "" THEN 0 else {s} END expression.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Simple conversion
Optimistic	Simple conversion
Full	Empty string as zero numeric

Concatenation of NULL

This setting specifies how to convert string concatenation with NULL. The following options can be set for this particular setting:

If Wrap with ISNULL function option is selected, every non-constant string_expression in concatenation will be wrapped with ISNULL(string_expression) and NULLs will be replaced with empty string.
Keep current syntax will maintain original syntax.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Keep current syntax
Optimistic	Keep current syntax
Full	Wrap with ISNULL function

Conversion of Empty strings

This setting specifies how to convert empty strings. The following options can be set for this particular setting:

Replace all string expressions with space
Replace empty string constants with space

To use the SQL Server/Azure SQL behavior, select Keep current syntax.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Keep current syntax
Optimistic	Keep current syntax
Full	Replace all string expressions with space

CONVERT and CAST binary string conversion

The conversion of binary values to numbers can return different values on different platforms. For example, on x86 processors, CONVERT(integer, 0x00000100) returns 65536 in ASE, but 256 in SQL Server. ASE also returns different values depending on byte order.

Use this setting to control how SSMA converts CONVERT and CAST expressions that contain binary values:

Select Simple conversion to convert the expressions without any warnings or correction. Use this setting if you know that the ASE server has a byte order that does not require any changes of the binary value.
Select Convert and correct to have SSMA convert and correct the expressions for use on SQL Server. The byte order in literal constants will be reversed. All other binary values (such as binary variables and columns) will be marked with errors. Use this value if you know that the ASE server has a byte order that requires changes to binary values.

Select Convert and mark with warning to have SSMA convert and correct the expressions, and mark all converted expressions with warning comments.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Convert and mark with warning
Optimistic	Simple conversion
Full	Convert and correct

Dynamic SQL

Use this setting to specify the type of message (Warning or Error) that SSMA shows in the Output or Error List pane when it encounters dynamic SQL in the ASE code.

If you select Convert and mark with warning, SSMA will convert the dynamic SQL and mark the statements with warning comments.
If you select Mark with error, SSMA will skip conversion and mark the statements with error comments.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Convert and mark with warning
Optimistic	Convert and mark with warning
Full	Mark with error

Equality check conversion

In SQL Server/Azure SQL, if the ANSI_NULLS setting is on, SQL Server/Azure SQL returns UNKNOWN when any equality comparison contains a NULL value. If ANSI_NULLS is off, equality comparisons that contain NULL values return true when the compared column and expression or two expressions are both NULL. By default (ANSINULL OFF) SAP ASE equality comparisons behave like SQL Server/Azure SQL with ANSI_NULLS OFF.

If you select Simple conversion, SSMA will convert the ASE code to SQL Server/Azure SQL syntax without extra checks for NULL values. Use this setting if ANSI_NULLS is OFF in SQL Server/Azure SQL or if you want to revise equality comparisons on a per-case basis.
If you select Consider NULL values, SSMA will add checks for NULL values by using the IS NULL and IS NOT NULL clauses.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Simple conversion
Optimistic	Simple conversion
Full	Consider NULL values

Format strings

SQL Server/Azure SQL no longer supports the format_string argument in PRINT and RAISERROR statements. The format_string argument allowed to put replaceable parameters directly in the string, and then replacing the parameters at runtime. Instead, SQL Server requires the full string by using either a string literal, or a string built by using a variable. For more information, see the PRINT (Transact-SQL) topic.

When SSMA encounters a format_string argument, it can either build a string literal using the variables or create a new variable and build a string by using that variable.

To use a string literal for PRINT and RAISERROR functions, select Create new string.

In this mode, if a PRINT or RAISERROR statement does not use placeholders and local variables, the statement is unchanged. Double percent characters (%%) are changed to a single percent character % in PRINT string literals.

If a PRINT or RAISERROR statement uses placeholders and one or more local variables, such as in the following example:
```
PRINT 'Total: %1!%%', @percent
```
SSMA will convert it to the following syntax:
```
PRINT 'Total: '+ CAST(@percent AS varchar(max)) + '%'
```
If format_string is a variable, such as in the following statement:
```
PRINT @fmt, @arg1, @arg2
```
SSMA cannot do a simple string conversion, and must create a new variable:
```
DECLARE @print_format_1 varchar(max)
SET @print_format_1 =
    REPLACE (@fmt, '%%', '%')
SET @print_format_1 =
    REPLACE (@print_format_1, '%1!',
    CAST (@arg1 AS varchar(max)))
SET @print_format_1 =
    REPLACE (@print_format_1, '%2!',
    CAST (@arg2 AS varchar(max)))
PRINT @print_format_1
```
When it uses Create new string mode, SSMA assumes that the SQL Server option CONCAT_NULL_YIELDS_NULL is OFF. Therefore, SSMA does not check for null arguments.
To have SSMA build a new variable for each PRINT and RAISERROR statement, and then use that variable for the string value, select Create new variable.

In this mode, if a PRINT or RAISERROR statement does not use placeholders and local variables, SSMA replaces all double percent characters (%%) with single percent characters to comply with SQL Server/Azure SQL syntax.

If a PRINT or RAISERROR statement uses placeholders and one or more local variables, such as in the following example:
```
PRINT 'Total: %1!%%', @percent
```
SSMA will convert it to the following syntax:
```
DECLARE @print_format_1 varchar(max)
SET @print_format_1 = 'Total: %1!%'
SET @print_format_1 =
    REPLACE (@print_format_1, '%1!',
    ISNULL(CAST (@percent AS VARCHAR(max)), ''))
PRINT @print_format_1
```
If format_string is a variable, such as in the following statement:
```
PRINT @fmt, @arg1, @arg2
```
SSMA creates a new variable as follows, checking for null values in each argument:
```
DECLARE @print_format_1 varchar(max)
SET @print_format_1 =
    REPLACE (@fmt, '%%', '%')
SET @print_format_1 =
    REPLACE (@print_format_1, '%1!',
    ISNULL(CAST (@arg1 AS varchar(max)),''))
SET @print_format_1 =
    REPLACE (@print_format_1, '%2!',
    ISNULL(CAST (@arg2 AS varchar(max)),''))
PRINT @print_format_1
```

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Create new string
Optimistic	Create new string
Full	Create new variable

Insert an explicit value into a timestamp column

SQL Server/Azure SQL does not support inserting explicit values into a timestamp column.

To exclude timestamp columns from INSERT statements, select Exclude column.
To print an error message every time that a timestamp column is in an INSERT statement, select Mark with error. In this mode, INSERT statements will not be converted and will be marked with error comments.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Exclude column
Optimistic	Exclude column
Full	Mark with error

Store temporary objects defined in procedures

This setting specifies if the temporary objects definitions which appear in the procedures should be stored in the source metadata during conversion.

Select Yes to store into metadata.
Select No if the objects need not be stored.

Mode	Value
Default	Yes
Optimistic	Yes
Full	No

Proxy table conversion

Specifies if ASE proxy tables are converted to SQL Server/Azure SQL tables, or are not converted and the code is marked with error comments.

Select Convert to convert proxy tables to regular tables.
Select Mark with error to simply mark the proxy table code with error comments.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Mark with error
Optimistic	Mark with error
Full	Mark with error

RAISERROR base message number

ASE user messages are stored in each database. SQL Server user messages are centrally stored and made available through the sys.messages catalog view. In addition ASE user messages start at 20000, but SQL Server error messages start at 50001.

This setting specifies the number to add to the ASE user message number to convert it to a SQL Server user message. If your SQL Server has user messages in the sys.messages catalog view, you might have to change this number to a higher value. This is so the converted message numbers do not conflict with existing message numbers.

Note the following:

ASE messages in the range 17000-19999 are from the sysmessages system table and are not converted.
If the message number that is referenced in the RAISERROR statement is a constant, SSMA will add the base message number to the constant to determine the new user message number.
If the message number that is referenced is a variable or expression, SSMA will create an intermediate local variable.
In Optimistic mode, SSMA assumes that the SQL Server option CONCAT_NULL_YIELDS_NULL is OFF and makes no checks for NULL arguments.
In Full mode, SSMA checks for NULL arguments.
RAISERROR with arg-list argument is not converted.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	30001
Optimistic	30001
Full	30001

System objects

Use this setting to specify the type of message (Warning or Error) that SSMA shows in the Output or Error List pane when it encounters the use of ASE system objects.

If you select Convert and mark with warning, SSMA will convert references to system objects and will mark statements with warning comments.
If you select Mark with error, SSMA will not convert references to systems objects and will mark statements with error comments.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Convert and mark with warning
Optimistic	Convert and mark with warning
Full	Mark with error

Unresolved identifiers

Use this setting to specify the type of message (Warning or Error) that SSMA shows in the Output or Error List pane when it cannot resolve an identifier.

If you select Convert and mark with warning, SSMA will attempt to convert references to unresolved identifiers and will mark statements with warning comments.
If you select Mark with error, SSMA will not convert references to unresolved identifiers and will mark statements with error comments.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Convert and mark with warning
Optimistic	Convert and mark with warning
Full	Mark with error

System functions section

CHARINDEX function

In ASE, CHARINDEX returns NULL only if all input expressions are NULL. SQL Server/Azure SQL will return NULL if any input expression is NULL.

To use the ASE behavior, select Replace function. All calls to CHARINDEX function is substituted with a call to either CHARINDEX_VARCHAR or CHARINDEX_NVARCHAR user defined function based on the type of parameters passed (created in the user database under the schema name s2ss) to emulate the SAP ASE behavior.
To use the SQL Server/Azure SQL behavior, select Keep current syntax.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Keep current syntax
Optimistic	Keep current syntax
Full	Replace function

DATALENGTH function

SQL Server/Azure SQL and ASE differ in the value returned by the DATALENGTH function when the value is a single space. In this case, SQL Server/Azure SQL returns 0 and ASE returns 1.

To use the ASE behavior, select Replace function. All calls to DATALENGTH function are substituted with CASE expression to emulate SAP ASE behavior.
To use the default SQL Server/Azure SQL behavior, select Keep current syntax.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Keep current syntax
Optimistic	Keep current syntax
Full	Replace function

INDEX_COL function

ASE supports an optional user_id argument to the INDEX_COL function; however, SQL Server/Azure SQL does not support this argument. If you use the user_id argument, this function cannot be converted to SQL Server/Azure SQL syntax.

To use the ASE behavior, select Convert function. If the code contains the user_id argument, SSMA will display an error.
To display an error message every time that INDEX_COL is encountered, select Mark with error. SSMA will not convert references to the function, and will mark the statement with error comments.

Mode	Value
Default	Mark with error
Optimistic	Mark with error
Full	Mark with error

INDEX_COLORDER function

SQL Server/Azure SQL does not have an INDEX_COLORDER system function.

To use the ASE behavior, select Convert function. All calls to INDEX_COLORDER function is substituted with a call to a user defined function with same name INDEX_COLORDER (created in the user database under the schema name s2ss) which emulates the SAP ASE behavior.
To print an error message every time that INDEX_COLORDER is encountered, select Mark with error. SSMA will not convert references to the function, and will mark the statement with error comments.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Mark with error
Optimistic	Mark with error
Full	Mark with error

LEFT and RIGHT Functions

LEFT and RIGHT functions in ASE behave differently for negative length parameter.

To use the ASE behavior, select Replace Function. The length parameter is then replaced with CASE expression which would return NULL for negative value.
To use the SQL Server behavior, select Keep current syntax.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Keep current syntax
Optimistic	Keep current syntax
Full	Replace function

Note

If the length parameter is a literal value and not a complex expression, the length value is always replaced with NULL irrespective of project setting.

NEXT_IDENTITY function

SQL Server/Azure SQL does not have an NEXT_IDENTITY system function.

To use the ASE behavior, select Convert Function. All calls to NEXT_IDENTITY function is substituted with expression (IDENT_CURRENT(parameter Value) + IDENT_INCR(parameter Value) which emulates the SAP ASE behavior.
To print an error message every time that NEXT_IDENTITY is encountered, select Mark with error. SSMA will not convert references to the function, and will mark the statement with error comments.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Mark with error
Optimistic	Mark with error
Full	Mark with error

Default/Optimistic/Full Mode: Mark with error

PATINDEX function

Specifies whether to convert PATINDEX function to match SAP ASE behavior. The point is that ASE trims trailing blanks in a search pattern. The workaround is to make a cast of value expression to a fixed length data type with a maximum precision and apply rtrim function to search pattern.

To use the ASE behavior select Use.
To use the default SQL Server/Azure SQL behavior, select Do not use.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Do not use
Optimistic	Do not use
Full	Use

REPLICATE function

The REPLICATE function repeats a string the specified number of times. In ASE, if you specify to repeat the string zero times, the result is NULL. In SQL Server/Azure SQL, the result is an empty string.

To use the ASE behavior, select Replace function. All calls to REPLICATE function is substituted with a call to either REPLICATE_VARCHAR or REPLICATE_NVARCHAR user defined function based on the type of parameters passed (created in the user database under the schema name s2ss) to emulate the SAP ASE behavior.
To use the default SQL Server/Azure SQL behavior, select Replace Function.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Replace function
Optimistic	Replace function
Full	Replace function

TRIM (LTRIM, RTRIM) function

This setting specifies whether to replace calls to TRIM, LTRIM and RTRIM functions with the SAP ASE-equivalent syntax functions or to keep the current syntax. The following options are present for this particular setting:

Replace function
Keep current syntax

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Replace function
Optimistic	Replace function
Full	Replace function

SUBSTRING function

In ASE, the function SUBSTRING(expression, start, length) returns NULL if a start value greater than the number of characters in expression is specified, or if length equals zero. In SQL Server/Azure SQL, the equivalent expression returns an empty string.

To use the ASE behavior, select Replace function. All calls to SUBSTRING function is substituted with a call to SUBSTRING_VARCHAR or SUBSTRING_NVARCHAR or SUBSTRING_VARBINARY user defined function based on the type of parameters passed (created in the user database under the schema name s2ss) to emulate the SAP ASE behavior.
To use the SQL Server/Azure SQL behavior, select Keep current syntax.

When you select a conversion mode in the Mode box, SSMA applies the following setting:

Mode	Value
Default	Keep current syntax
Optimistic	Keep current syntax
Full	Replace function

Tables section

Add primary key

Creates a new primary key in the SQL Server or Azure SQL table if an SAP ASE table has no primary key or unique index.

Mode	Value
Default	No
Optimistic	No
Full	Yes

Note

When connected to Azure SQL, it is Yes by default.

Jaa

Project Settings (Conversion) (SybaseToSQL)

Miscellaneous section

@@ERROR

Conversion of LIKE operator

CONVERT or CAST empty strings to numeric types

Concatenation of NULL

Conversion of Empty strings

CONVERT and CAST binary string conversion

Dynamic SQL

Equality check conversion

Format strings

Insert an explicit value into a timestamp column

Store temporary objects defined in procedures

Proxy table conversion

RAISERROR base message number

System objects

Unresolved identifiers

System functions section

CHARINDEX function

DATALENGTH function

INDEX_COL function

INDEX_COLORDER function

LEFT and RIGHT Functions

NEXT_IDENTITY function

PATINDEX function

REPLICATE function

TRIM (LTRIM, RTRIM) function

SUBSTRING function

Tables section

Add primary key

See Also

Palaute

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