Skills required for Oracle test 1Z0-001.

Oracle has specified more than twenty objectives for 1Z0-001 (Introduction to Oracle: SQL and PL/SQL) test. Following are some important areas over which one should have good command before taking the test: Overview of relational databases, SQL, and PL/SQL. Writing basic SQL statements.......
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Things to practice for Oracle test 1Z0-001.

One should have a good knowledge about RDBMS concepts, SQL, and PL/SQL before taking the 1Z0-001 (Introduction to Oracle: SQL and PL/SQL) test, as this test focuses on one's capability to design relational databases and write various types of SQL and PL/SQL statements to interact with databases.......
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What is a trigger?

Trigger A trigger is a kind of procedure that executes implicitly when a table or view is modified or some user actions or database system actions occur. Similar to a stored procedure, a trigger stored in the database can include SQL and PL/SQL or Java statements to run as a unit and can......
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What is PL/SQL?

PL/SQL is Oracle's procedural extension to SQL, which is the standard database access language. PL/SQL is an advanced fourth-generation programming language (4GL) and offers seamless SQL access, tight integration with the Oracle server and tools, portability, security, and modern software......
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What is the structure of a PL/SQL block?

Procedural Language/Structured Query Language (PL/SQL) is a procedural language extension to SQL, the standard data access language for relational databases. PL/SQL is not an Oracle product in its own right; rather, it is a technology used by Oracle server and certain Oracle tools. PL/SQL......
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How is top-n analysis performed?

Top-n analysis is performed using a top-n analysis query. Following is the structure of a top-n analysis query: SELECT [column_list], ROWNUM FROM (SELECT [column_list] FROM table ORDER BY top-n_column) WHERE ROWNUM <= n; A top-n analysis query comprises the following elements: A......
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What is a constraint?

A constraint enforces the integrity of a database. It defines rules regarding the values allowed in the columns of a table. A constraint is the standard mechanism for enforcing integrity. Using constraints is preferred to using triggers, rules, and defaults. Most of the RDBMS databases support......
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What is a primary key?

A table usually has a column or combination of columns whose values uniquely identify each row in the table. This column (or columns) is called the primary key. Primary key ensures that no duplicate or null values are entered in the column (or columns) defined as primary key columns. This......
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What is a role?

A role is a named group of privileges such as object, system, and role privileges, which can be granted to a user or to another role. A user can be assigned several roles, and a single role can be granted to several users. A role is created using the CREATE ROLE statement. Syntax: CREATE......
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What is an index?

An index is a data structure that improves the performance of queries issued against a table. An index can be created for one or more columns of a table. Once created, an index is automatically updated and used by the database. It is logically and physically independent of data. The table or......
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