SQL

SQL (Structured Query Language) is a standard language used to operate relational databases. It includes operations such as database creation, retrieving and modifying data, granting privileges to data.

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JSON_TABLE Options: Error Handling, Nested Path

Various options that can be used with JSON_TABLE query operator to select JSON data as relational rows and columns: ERROR ON ERROR, FOR ORDINALITY, NESTED PATH etc.

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JSON Conditionals: JSON_EXISTS, JSON_TEXTCONTAINS

Implement true/false tests on JSON documents in Oracle database 12c using JSON conditional logic: JSON_EXISTS and JSON_TEXTCONTAINS.

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Querying JSON Data in Oracle: SQL/JSON Query Functions, Dot Notation

Querying JSON data in Oracle 12c using various query approaches: simple SQL, SQL/JSON functions (JSON_QUERY, JSON_VALUE, JSON_TABLE), dot-notation syntax.

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SQL XML in Oracle: Generating XML from Relational Data

Generating XML from Relational Data using Oracle SQL/XML

How to generate XML from relational data using a combination of Oracle SQL/XML functions such as XMLELEMENT, XMLATTRIBUTES, XMLFOREST, XMLAGG, XMLSERIALIZE.

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SQL: Compare Two Tables for Differences in Data

How to compare two tables that share the same structure, to identify data differences between the two tables: missing rows, extra rows, or mismatch in attribute values.

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DATE Format SQL for Dates Stored as Strings

Convert VARCHAR2 to DATE with appropriate format masks, for comparing two dates stored as strings with different DATE formats in the database.

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INNER JOIN and OUTER JOIN Explained

Overview of INNER JOIN and OUTER JOIN in Oracle, with examples, memory aids and a further drilldown of INNER JOIN and OUTER JOIN types.

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Grant SELECT on V$ Views

Grant SELECT on V$ views to allow non-admin database users to query SYS-owned V$ views (dynamic performance views) such as V$INSTANCE or V$SESSION.

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How to Find out Your Oracle Database Version

Three ways to find out your Oracle database version in SQL and PL/SQL: using V$VERSION, V$INSTANCE, or DBMS_DB_VERSION constants.

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UNPIVOT in Oracle 11G to Select Columns As Rows

You can easily transpose table columns to rows in Oracle 11G+ using the UNPIVOT clause is SQL. A comparison of the pre-11G DECODE solution with the 11G+ UNPIVOT method.

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