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Blocks & Variables
Anonymous block DECLARE section Variable assignment Constants Anchored %TYPE Anchored %ROWTYPE Nested blocks Labels NULL statement DBMS_OUTPUT
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SQL in PL/SQL
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Exceptions
Predefined exception User-defined exception RAISE RAISE_APPLICATION_ERROR WHEN OTHERS SQLCODE and SQLERRM Exception propagation PRAGMA EXCEPTION_INIT Nested exception handler Reraising exception
Procedures & Functions
CREATE PROCEDURE IN parameter OUT parameter IN OUT parameter CREATE FUNCTION RETURN statement Default parameters Named notation Local subprogram Overloading
Packages
Package specification Package body Public procedure Private procedure Package variable Package initialization Package constant Package cursor Package overloading Forward declaration
Collections & Records
RECORD type Associative array Nested table VARRAY FIRST and LAST NEXT and PRIOR COUNT collection EXTEND DELETE collection element BULK COLLECT
Advanced PL/SQL
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PL/SQL / Blocks & Variables

Nested blocks

Learn Nested blocks in PL/SQL through a focused explanation, a dedicated construct-specific example, an engineering boundary, and a mastery check.

10 min read • Beginner

Nested blocks is an atomic PL/SQL topic inside Blocks & Variables. This lesson focuses on how the Nested blocks construct is written, what it changes, and when it is the right tool.

Trace the example line by line. Identify the exact syntax for Nested blocks, the input state before it runs, and the resulting value, control flow, database state, hardware behavior, or runtime effect afterward. Neighboring lessons use different constructs rather than renamed copies of this one.

Topic-specific example

plsql-01-07-nested-blocks.sql
plsql Try It Live 
DECLARE v_msg VARCHAR2(20):='outer'; BEGIN DECLARE v_msg VARCHAR2(20):='inner'; BEGIN DBMS_OUTPUT.PUT_LINE(v_msg); END; DBMS_OUTPUT.PUT_LINE(v_msg); END; /
Edge case / engineering note

For Nested blocks, test the boundary that belongs to this exact feature rather than a generic failure case. Check invalid or empty input, NULL/unknown state, numeric limits, transaction or exception behavior, synthesis/runtime constraints, ownership/permission rules, or backtracking/control-flow effects where they apply.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

Nested blocks Mastery Check →
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