One of the most interesting algorithms of research is binary search algorithm. This is the fastest algorithm (algorithm of binary trees apart) to search a data inside a group of elements. In fact it runs in a worst log2(x) comparisions before to find (or not) the data. The only prerequisite is : the set of…
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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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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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Sometimes can be useful to produce a CSV file semicolon separated from a table. Here a simple dynamic procedure that works without write sql scripts pl sql code. Just put in some parameters and execute it from everywhere. With little customizations you can add a parameter for separator, add “” for strings, columns to avoid…
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The AUTHID property of a stored PLSQL unit, determines the authorization under which a PLSQL subprogram operates at run-time. You can use two clause: . CURRENT_USER : when the subprogram is executed , it will run using the rights of the person that invoked the code, not with the creator’s rights . DEFINED : when…
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An index by table is an associative array. An associative array never has more than two columns: the variable being indexes and the index value. However you can combine a record with an associative array to tie multiple values to the same index. In this case the array still has a variable and an…
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