| Table A-1 compares the datatypes supported by Sybase Adaptive Server to those supported by Microsoft SQL Server. While there is significant overlap in the types offered , a few types differ in meaning or are missing on one of the platforms. Where differences in the types exist, they'll be listed in the table. Types that are not listed within the table should be considered identical on both platforms. Table A-1. Sybase Adaptive Server datatypes | Sybase adaptive server datatype | Microsoft SQL Server datatype | Notes | | N/A | BIGINT | Usage of decimal(19,0) as an equivalent to BIGINT will allow storage of values within the same range. | | BINARY | BINARY | Describes a fixed-length binary value up to 255 bytes in size . In contrast, Microsoft SQL Server can store 8,000 bytes. | | CHAR(N ) | CHAR(N) | Holds fixed-length character data up to the database's page size in length. | | DATETIME | DATETIME | Holds date and time data within the range of 1753-01-01 00:00:00 through 9999-12-31 23:59:59. The DATETIME type can store milliseconds with a granularity of 1/300 second. | | NCHAR(N) | N/A | Holds fixed-length character strings in the national character set up to the database's page size in length. In contrast, Microsoft SQL Server's NCHAR datatype stores Unicode character strings. | | N/A | NTEXT | Holds Unicode text passages up to 1,073,741,823 characters in length. | | NVARACHAR(N) | N/A | Holds variable-length character strings in the national character set up to the database's page size in length. In contrast, Microsoft SQL Server's NVARACHAR datatype stores Unicode character strings. | | TIMESTAMP | ROWVERSION | A unique number within a database that is updated whenever a row is updated. | | SMALLDATETIME | SMALLDATETIME | Holds date and time data within the range of 1900-01-01 00:00 through 2079-12-31 23:59. Unlike Microsoft SQL Server, Sybase cannot hold dates with second resolution in a SMALLDATETIME . | | N/A | SQL_VARIANT | Sybase has no weakly typed storage type like SQL Server's SQL_VARIANT . | | UNICHAR | NCHAR(N) | Stores fixed-length, Unicode character strings up to the database's page size in length. | | N/A | UNIQUEIDENTIFIER | Represents a value that is unique across all databases and all servers. | | UNIVARCHAR | NCHAR(N) | Stores variable-length, Unicode character strings up to the database's page size in length. | | VARBINARY(N) | VARBINARY(N) | Describes a variable-length binary value up to 255 bytes in size. In contrast, Microsoft SQL Server can store up to 8,000 bytes. | | VARCHAR(N) | VARCHAR(N) | Holds fixed-length character data up to the database's page size in length. |
The primary differences between the types offered by SQL Server and Sybase are the storage sizes, precision, and default meaning of the NCHAR type. When converting data from one platform to the other, it is important to observe these subtle differences to avoid data truncation or corruption. |
