![]() ![]() ![]() The column name 'process' of STV_SESSIONS table contains the Process ID for the session. For more on STV_SESSIONS, please refer to below link The system table STV_SESSIONS can be used to view information about the active user sessions for Amazon Redshift. (You can't specify a name for this schema.) This temporary schema becomes the first schema in the search path, so the temporary table takes precedence over the permanent table unless you qualify the table name with the schema name to access the permanent table. The temporary table is created in a separate, session-specific schema. The temporary table can have the same name as a permanent table. The table is automatically dropped at the end of the session in which it is created. Disadvantages: More complicated dynamic SQL code, need to resolve conflicts between sessions by using unique table names.A temporary table that is visible only within the current session. Then you can use user-defined functions to get and set variable values:ĬREATE PROCEDURE pack1_name_set ( VARCHAR (30 ) ) AS EXEC ( 'UPDATE #pack1_vars_' + + ' SET name = ' '' + + '' '' ) CREATE PROCEDURE pack1_name_get ( VARCHAR (30 ) OUTPUT ) AS BEGIN DECLARE NVARCHAR (100 ) SET = N 'SELECT = name FROM #pack1_vars_' + CAST ( AS VARCHAR ) EXEC sp_executesql, = N VARCHAR(30) OUTPUT', = OUTPUT ENDĪn example of procedure that uses package variable in SQL Server:ĪS BEGIN DECLARE VARCHAR (30 ) EXEC pack1_initĮXEC pack1_name_get OUTPUT PRINT pack1_name_set 'New name' ENDĪdvantages: Flexible solution, no need to change applications, data are cleaned automatically. ![]() WHERE id = object_id ( 'tempdb.#pack1_vars_' + CAST ( AS VARCHAR ) ) and xtype = 'U' ) BEGIN EXEC ( 'CREATE TABLE #pack1_vars_' + + ' (name VARCHAR(30), cdate DATETIME)' ) EXEC ( 'INSERT INTO #pack1_vars_' + + ' VALUES (' 'Company Name' ', GETDATE())' ) END END You can use function to generate unique table names in each session.īefore you can use variables, you have to call initialization code that creates and initializes the table in procedures or functions that use the variable.ĪS BEGIN IF NOT EXISTS ( SELECT * FROM tempdb. Unique global temporary table for each sessionĮvery session should create its own global temporary table for each package containing variables. In contract to local temporary tables, once you create a global temporary table, it becomes visible in any procedures and application.īut the global temporary table is also visible in other sessions, so you need to add some logic to avoid conflicts. You can use global temporary tables to emulate Oracle package variables. Then you can use SQL SELECT and UPDATE statements to retrieve and update values:ĭECLARE VARCHAR (30 ) SELECT =name FROM #pack1_vars UPDATE #pack1_vars SET name = 'New value'Īdvantages: Relatively easy to use, no conflicts with other sessions, data are cleaned automatically Disadvantages: Needs creation by each application, not easy to track and manage in case of large number of local temporary tables (a lot of packages with variables). INSERT INTO #pack1_vars VALUES ( 'Company Name', GETDATE ( ) ) But due to visibility limitations (see above), you have to create and initialize a local temporary table in the application (for example, right after connection). You can use local temporary tables to emulate Oracle package variables. ![]() Package variables are not shared between Oracle sessions (connections), each session has its own copy of data in the variables. In Oracle, package variables are global variables that can store values until the end of the session, and shared between all procedures and functions in the package. No errors shown during procedures creation, but we get a run-time error. Msg 208, Level 16, State 1, Procedure sp_use_tempt, Line 6 The local temporary table cannot be referenced by the stored procedure or application that called the stored procedure that created the local temporary table. This means that this local temporary table can be referenced only by nested stored procedures. If a local temporary table created in a stored procedure, it is dropped automatically when the stored procedure is finished. So if you create a local temporary table in one session, you cannot access it in other sessions. In SQL Server, local temporary tables are visible only in the current session. A local temporary table is created using CREATE TABLE statement with the table name prefixed with single number sign (#table_name). ![]()
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