The key feature that made SQL Server attractive from the start was its high performance due to shared log writes, clustered indexes and a small memory footprint per user.
Sybase provides native low-level programming interfaces to its database server which uses a protocol called Tabular Data Stream.
[3] Sybase 11.5 added Asynchronous prefetch, case expression in sql, the optimizer can use a descending index to avoid the need for a worktable and a sort.
Indexes could now be created in descending order on a column, readpast concurrency option and repeatable read transaction isolation were added.
A lock timeout option and task-to-engine affinity were added, query optimization is now delayed until a cursor is opened and the values of the variables are known.
In 2001, ASE 12.5 was released, providing features such as dynamic memory allocation, an EJB container, support for XML, Secure Sockets Layer (SSL) and LDAP.
It included support for partitioning table rows in a database across individual disk devices, and "virtual columns" which are computed only when required.
Deferred name resolution for user-defined stored procedures, FIPS 140-2 login password encryption, incremental data transfer, bigdatetime and bigtime datatypes and tempdb groups were also added.
[7] It included support for: New Security features - Application Functionality Configuration Groups, a new threaded kernel, compression for large object (LOB) and regular data, End-to-End CIS Kerberos Authentication, Dual Control of Encryption Keys and Unattended Startup and extension for securing logins, roles, and password management, Login Profiles, ALTER... modify owner, External Passwords and Hidden Text, Abstract Plans in Cached Statements, Shrink Log Space, In-Row Off-Row LOB, using Large Object text, unitext, and image Datatypes in Stored Procedures, Using LOB Locators in Transact-SQL Statements, select for update to exclusively lock rows for subsequent updates within the same transaction, and for update-able cursors, Non-materialized, Non-null Columns with a default value, Fully Recoverable DDL (select into, alter table commands that require data movement, reorg rebuild), merge command, Expanded Variable-Length Rows, Allowing Unicode Noncharacters.
It included support for partition locking, CIS Support for HANA, Relaxed Query Limits, Query Plan Optimization with Star Joins, Dynamic Thread Assignment, Sort and Hash Join Operator improvements, Full-Text Auditing, Auditing for Authorization Checks Inside Stored Procedures, create or replace functionality, Query Plan and Execution Statistics in HTML, Index Compression, Full Database Encryption, Locking, Run-time locking, Metadata and Latch enhancements, Multiple Trigger support, Residual Data Removal, Configuration History Tracking, CRC checks for dump database and the ability to calculate the transaction log growth rate for a specified time period.
'master' database holds critical system related information that includes, logins, passwords, and dataserver configuration parameters.
The "Platform edition" includes licenses enabling several unspecified features (probably the newer, in memory high performance options and the disaster recovery functionality (near synchronous replication to a hot spare)) [8] The "express edition" (used to be free, but limited to four server engines and 50 GB of disk space per server) is no longer available after version 16.0 SP03.