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(Workplace UNIX) Introducing SQL Server |
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| Glossary |
A function that works on a set of cells to produce a single answer or set of answers, one for each subset of cells.
A name that allows a SQL Server user to be known in a database by another name.
A value supplied to a function or procedure that is required to evaluate the function.
An expression that contains only numeric operands and returns a single numeric value. In Transact-SQL, the operands can be of any numeric datatype. They can be functions, variables, parameters, or they can be other arithmetic expressions. Synonymous with numeric expression.
A process that runs every time SQL Server is stopped and restarted. The process ensures that all transactions that have completed before SQL Server went down are brought forward and all incomplete transactions are rolled back.
A copy of a database or transaction log, used to recover from a media failure.
The tables on which a view is based. Also called "underlying" tables.
One or more Transact-SQL statements terminated by an end-of-batch signal, which submits them to the SQL Server for processing.
An association between a default or rule and a database table column or a user-defined datatype.
A method that Client-Library applications can use to browse through database rows, updating their values one row at a time. Cursors provide similar functionality and are generally more portable and flexible.
A wide variety of functions that take one or more parameters and return results. The built-in functions include mathematical functions, system functions, string functions, text functions, date functions, and a type conversion function They can be used in Transact-SQL statements.
The utility for copying data in and out of databases, called bcp.
A routine that Open Client calls in response to a triggering event, known as a callback event.
In Open Client, an occurrence that triggers a callback routine.
A feature of a client/server connection that determine the types of client requests and server responses permitted for that connection.
A delete operation implemented with a trigger that deletes data from a table based on a deletion from another table. A cascading delete is often performed to delete detail data when master data is deleted in a master/detail application.
An expression that returns a single character-type value; can include literals, concatenation operators, functions, and column identifiers.
A set of specific (usually standardized) characters with an encoding scheme that uniquely defines each character. ASCII and ISO 8859-1 (Latin 1) are two common character sets.
Changing the encoding scheme of a set of characters on the way into or out of SQL Server. Conversion is used when SQL Server and a client communicating with it use different character sets.
A limit on the values users can insert into a column of a table. A check constraint specifies a search condition, which must not evaluate to FALSE for the value being inserted through an insert, update, or bcp.
In client/server systems, the part of the system that sends requests to servers and processes the results of those requests.
Part of Open Client; a collection of routines for use in writing client applications. Client-Library is alibrary designed to accommodate cursors and other advanced Sybase features.
A column contains an individual value within a row. Columns are ordered and named.
Limits the acceptable values for a specified column.
An instruction that specifies an operation to be performed by the computer. Each command or SQL statement begins with a keyword, such as insert, that names the basic operation performed.
A hidden Client-Library structure that defines a client/server connection within a context.
An expression that always returns the same value. For example, "3 + 5" is a constant expression.
A CS-Library hidden structure that defines an application "context," or operating environment, within a Client-Library application.
Programming-like constructs (such as if, else, while, goto, label:) provided by Transact-SQL to enable the user to control the flow of execution of Transact-SQL statements.
See character set conversion.
The row to which a cursor points. A fetch against a cursor retrieves the current row.
A symbolic name associated with a Transact-SQL select statement through a declaration statement. A cursor behaves much like a file pointer to a series of file records, where the cursor acts as a pointer to the query results.
The process of setting up databases and creating database objects such as tables, indexes, rules, defaults, constraints, procedures, triggers, and views.
In SQL Server, the system tables that contain descriptions of the database objects and how they are structured.
Adding, deleting, or changing information in the database with the insert, delete, and update commands.
A set of related data tables and other database objects that are organized and presented to serve a specific purpose.
A device dedicated to the storage of the objects that make up databases. The database device can be any piece of disk or a file in the file system that is used to store databases and database objects.
One of the components of a database: table, view, index, procedure, trigger, column, default, constraint or rule.
The user who creates a database or who has been assigned ownership by the creator of a database. A Database Owner has control over all the database objects in that database. The login name for the Database Owner is "dbo".
Specifies what kind of information each column holds and how the data is stored. System datatypes include char, int, money, and so on. You can construct your own datatypes in SQL Server based on the SQL Server system datatypes.
A function that displays information about dates and times, or manipulates date or time values. The five date functions are getdate, datename, datepart, datediff, and dateadd.
Part of Open Client; a collection of routines for use in writing client applications.
1. The database object that specifies a value that SQL Server inserts for a column when no value is provided. 2. The option used when you do not explicitly specify an option.
The database accessed by default when you log into SQL Server.
1. The language that displays that user's prompts and messages, as set with the sp_modifylogin system procedure or the language option of the set command. 2. The language that SQL Server uses to display prompts and messages users unless you chooses a different language.
The deletion of one or more rows from a database table.
See database device.
Reads and writes performed by SQL Server to a database device.
A duplicate of a SQL Server database device. All writes to the device being mirrored are copied to a separate physical device, making the second device an exact copy of the device being mirrored. If one of the devices fails, the other contains an up-to-date copy of all transactions.
1. A backup copy of a database or a transaction log. 2. The process of creating a backup.
Interleaving of dump data across several dump volumes.
A Client-Library feature that allows an application to execute SQL statements containing variables whose values are determined at run time.
A computation, column data, built-in function, or subquery that can be evaluated.
A key column in a table that logically depends on a primary key column in another table; a column (or combination of columns) whose values are required to match a primary key in some other table or be NULL.
A user-specified threshold that specifies the amount of space on a segment, and the action to be taken when the amount of space available on that segment is less than the specified space.
See built-in functions.
An application that acts as an intermediary for clients and servers that cannot communicate directly. Acting as both client and server, a gateway application passes requests from a client to a server and returns results from the server to the client.
System-defined variables that SQL Server updates on an ongoing basis. For example, @@error contains the last error number generated by the system.
If the user name "guest" exists in the sysusers table of a database, any user with a valid SQL Server login can use that database, with limited privileges.
A string of characters used to identify a database object, such as a table name or column name.
The column in a table that contains a system-generated value that uniquely identifies each row within that table.
A storage structure that speeds up data retrieval by pointing SQL Server to where a table column's data is stored on disk.
The addition of a row to a database table.
A signed 32-bit integer value.
A basic operation in a relational database management system. A join links the rows in two or more tables by comparing the values in specified columns.
A column used to identify a row, often used as the index column for a table.
A word or phrase that is reserved for exclusive use by Transact-SQL. Also known as a reserved word.
1. A copy of a database, used to recover from a media failure. 2. The process of copying a database backup to recover a database.
The geographical environment in which a program is running. The locale determines the language, sort order, and date and time formatting conventions.
A character string that represents a language and character set pair. Locale names are listed in the locales file. SQL Server predefines some locale names, but you can define additional locale names and add them to the locales file.
The process of setting up an application to run in a specific native language environment. An application that is localized typically generates messages in a local language and character set and uses local datetime formats.
The name a user uses to log into SQL Server. A login is valid if SQL Server has an entry for that user in the system table syslogins.
The system database that controls the user databases and the operation of SQL Server as a whole. The master database keeps track of such information as user accounts, ongoing processes, and system error messages.
The allocation of memory to SQL Server; a SQL Server configuration option.
See disk mirror.
A template for new user databases. Each time the create database command is issued, SQL Server makes a copy of model.
A character set that includes characters encoded using more than one byte. EUCJIS and Shift-JIS are examples of character sets that include several types of characters represented by multiple bytes in a Japanese language environment.
Having no explicitly assigned value. NULL is not equivalent to zero, or to blank.
See database object.
A client application that communicates requests to SQL Server.
A group of programs that translates your commands to the computer, helping you perform such activities as creating files, running programs, and printing documents.
A SQL Server user in charge of performing server-wide database operations such as backing up and restoring databases.
The principal query in a statement containing a subquery.
1. An argument to a stored procedure. 2. A value passed between routines.
The authority to perform a specified action on a certain object, such as executing a stored procedure, or running a particular command.
The maximum number of digits that can be represented in a decimal, numeric, or float column.
The column or columns whose values uniquely identify a row in a table.
See permission.
See stored procedure.
A database object whose name is preceded by the name of the database and the object owner.
1. A request for the retrieval of data. 2. Any SQL statement that manipulates data.
The process of rebuilding one or more databases from database dumps and log dumps. See also automatic recovery.
The rules governing data consistency, specifically the relationships among the primary keys and foreign keys of different tables. SQL Server addresses referential integrity with user-defined triggers.
A constraint requiring that data inserted into a "referencing" table that defines the constraint must have matching values in a "referenced" table.
A mechanism for executing a stored procedure on a remote SQL Server.
A SQL Server user's authorization level: System Administrator, System Security Officer, or Operator. A user may be assigned more than one role, and more than one user may have the same role.
A Transact-SQL statement used within a user-defined transaction (before a commit transaction has been received) to undo any changes that were made to the database.
A set of related columns that describes a specific entity in a table or view. Rows are unordered.
A SQL Server specification that controls the domain of acceptable values for a table column or a user-defined datatype.
See System Administrator.
A marker inside a user-defined transaction that specifies a point to which you can roll back (cancel) a transaction. When you roll back the transaction to the savepoint, all statements before the savepoint are committed, and all statements after the savepoint are cancelled.
The number of digits to the right of the decimal point in a numeric or decimal datatype. The scale of a datatype cannot be greater than its precision.
A label that points to one or more database devices that are available to a specific database. You use segments to control the placement of tables and indexes on specific database devices.
The list of data to be retrieved by a select statement.
In client/server systems, the part of the system that processes client requests and returns results to clients.
The severity of an error condition. Errors with severity levels of 19 and above are fatal errors.
Area of SQL Server memory that holds information required to coordinate multiple operating system processes and make them appear to clients as a single SQL Server process.
Used by SQL Server to determine the order in which character data is sorted. Also called collating sequence.
The server in Sybase's "Client-Server" architecture. SQL Server manages multiple databases and multiple users, keeps track of the actual location of data on disks, maintains mapping of logical data description to physical data storage, and maintains data and procedure caches in memory.
An instruction given to SQL Server.
A series of Transact-SQL statements enclosed between the keywords begin and end; the statements are treated as a unit in control-of-flow constructs such as if...else and while.
A collection of preprocessed Transact-SQL statements stored under a name in SQL Server. SQL Server-supplied stored procedures are called system procedures.
A select statement that is nested inside another select, insert, update, or delete statement, or inside another subquery.
The user in charge of administrative activities unrelated to specific applications. These activities include managing disk storage, granting create database permission to SQL Server users, and running diagnostic and repair functions.
The databases that SQL Server automatically installsūthe master database (master), which controls user databases and the operation of the SQL Server; the temporary database (tempdb), used for temporary tables; the system procedures database (sybsystemprocs) and the model database (model) which is used as a template to create new user databases.
A function that returns information from the system tables.
Stored procedures that SQL Server supplies for use in system administration. These procedures are provided as shortcuts for retrieving information from the system tables or as mechanisms for accomplishing database administration and other activities that involve updating system tables.
The user in charge of security-sensitive activities on SQL Server, such as creating, dropping, and locking user accounts, and changing passwords of other users. See also role.
A SQL Server data dictionary table. The system tables keep track of information about the SQL Server as a whole and about each user database.
A database object used to store data. Each row in a table describes one occurrence of an entity, and each column describes one characteristic of the entity.
A constraint that limits values on more than one column of a table.
Space usage values of database and log segments. When free space in a segment falls below a threshold value, a stored procedure executes.
An enhanced version of Structured Query Language (SQL). Applications use Transact-SQL to communicate with SQL Server.
A mechanism for ensuring that a set of actions is treated as a single unit of work.
A system table (syslogs) in which all changes to the database are recorded.
A special form of stored procedure that goes into effect when a user gives a change command, such as insert, delete, or update, to a specified table or column. The trigger action is the action for which the trigger is specified, and the trigger conditions are the conditions that cause the trigger to take effect.
A function used to convert expressions of one datatype into another datatype, whenever these conversions are not performed automatically by SQL Server.
An addition, deletion, or change to data, involving the insert, delete, truncate table, or update statements.
A lock granted to an updating process while a table is being searched for qualifying rows. When the actual update is performed, the qualifying rows are locked exclusively.
A definition of the type of data a column can contain, created by the user and defined in terms of the existing system datatypes. Rules and defaults can be bound to user-defined datatypes (but not to system datatypes).
A block of Transact-SQL statements delimited by a begin transaction and commit transaction statement, allowing users to group any number of simple transactions as a single unit that can be completed or canceled.
A named piece of memory, used to store a value.
A virtual table consisting of selected columns and rows from one or more tables or other views.
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