In Pl Sql exists a lot of data types : varchar2, number, float, double, boolean, etc, but it may happen that you want to use a structure that contains several types of data, we call it Record type. It’s a simply a new data type. Record type is formed by a group of one or…
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In PL SQL exists an efficient and adaptable collection of data: Nested table. Nested table is similar to one dimensional array but with some differences : An array has declare number of element – Nested table not. The size of nested table can increase using extend method. An array has always consecutive elements – Nested…
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PL/SQL issues an implicit cursor whenever you execute a SQL statement directly in your code, as long as that code does not employ an explicit cursor. It is called an “implicit” cursor because you do not explicitly declare a cursor for the SQL statement. If you use an implicit cursor, Oracle performs the open, fetches,…
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Description: Goal search algorithm or search algorithm of the limit of a monotonically increasing sequence bounded above. 1) Purpose: Research of limit of a monotonically increasing sequence bounded above. 2) Example: Suppose to want to create a 10 meters high tower with a tolerance of 10 millimeters, having a given number of bricks, each of…
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To hide PlSql source code you can use both: dynamic obfuscation the wrap utility You might have to wrap some of yours PlSql objects just to provide the security of your code. Once wrapped, your code can’t be displayed from the static data dictionary views [ *_SOURCE ]. You can wrap the following types of…
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The execution flow can be divided into four stage. Not all Sql Statements will use all the stages: Parse: at the beginning the statement must be parsed, this mean check the syntax and associate it with the cursor. It also verifies if the privilege are correct and if the objects referenced really exists Bind:…
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System events are particular database states that can be used to fire a system trigger. Is possibile to create triggers for these events at DATABASE or SCHEMA level. When a triggering event occurs, the database will open an autonomous transaction scope, fire the trigger and commit any transaction imbedded in the trigger. The available system…
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