What is volatile table in DB2?

What is volatile table in DB2?

A VOLATILE table is one that is suppose to have widely fluctuating data and could, at any given moment, have no rows or may have millions of rows.

What is Syscat tables in DB2?

SYSTABLES is the system catalog table, while SYSCAT. TABLES is a system catalog view. It depends of what you need, but you may use SYSIBM.

How do you drop a table in DB2?

Db2 DROP TABLE

1. First, specify the name of the schema to which the table belongs. The schema is optional. If you skip it, the statement will delete the specified table in the current schema.
2. Second, specify the name of the table that you want to drop.

What is volatile attribute?

The VOLATILE attribute is used to designate a data object as being mapped to memory that can be accessed by independent input/output processes and independent, asynchronously interrupting processes. Code that manipulates volatile data objects is not optimized.

What is table type A in db2?

This makes sense because tables of type ‘A’ are an alias to another table. If you want to find the columns for a table of type ‘A’, look in the BASE_TABSCHEMA and BASE_TABNAME columns to find name of the schema and table that the alias is referencing. If you look up that table, it will be in syscolumns.

What happens to view when table is dropped in db2?

All views based on the table are marked inoperative. All privileges on the dropped table and dependent views are implicitly revoked. All referential constraints in which the table is a parent or dependent are dropped.

How do I delete a table in Cobol in db2?

Db2 DELETE

1. First, specify the name of the table from which you want to delete data.
2. Second, use a condition in the WHERE clause to specify which rows to delete. All rows that cause the condition to evaluate to true will be deleted.

What is Db2 LUW?

Db2 LUW is the “Common Server” product member of the Db2 family, designed to run on most popular operating systems. By contrast, all other Db2 products are specific to a single platform. Db2 11.5 has native language support for Python, Ruby, Go, Java, PHP, Node. js and Sequelize.

What is the use of volatile?

Volatile keyword is used to modify the value of a variable by different threads. It is also used to make classes thread safe. It means that multiple threads can use a method and instance of the classes at the same time without any problem. The volatile keyword can be used either with primitive type or objects.

What does volatile do?

volatile is a qualifier that is applied to a variable when it is declared. It tells the compiler that the value of the variable may change at any time-without any action being taken by the code the compiler finds nearby.

Can a volatile table be used in DB2?

There are many applications that use DB2 in this way – Tivoli databases, ESB, and others. Within DB2, marking a table as volatile pushes db2 to use an index over a table scan even if the optimizer doesn’t recommend usage of an index. This doesn’t mean the best index will necessarily be chosen, but some index will.

What do you mean by a volatile table?

But not everyone knows what a volatile table is or what this does, so I thought I’d write a quick post on it. A true volatile table is one that is used only for transient data – data that is put into tables and then quickly removed, meaning that a table marked as volatile could have zero rows one minute, 40,000 the next, and then back to zero.

When to use for bit clause in DB2?

The FOR BIT DATA clause can be specified in any order with the other column constraints that follow. DB2SECURITYLABEL is the built-in distinct type that must be used to define the row security label column of a protected table.

What is the default value for db2securitylabel in SQL?

For a column of type DB2SECURITYLABEL, NOT NULL WITH DEFAULT is implicit and cannot be explicitly specified (SQLSTATE 42842) . The default value for a column of type DB2SECURITYLABEL is the session authorization ID’s security label for write access.