{
  "id": 9254260,
  "title": "Oracle SQL: Pseudo-Columns",
  "url": "https://urgent.news/2026/09/23/oracle-sql-pseudo-columns",
  "topic": "tech",
  "section": "Tech",
  "published": "2026-09-23T03:03:55.000Z",
  "source": {
    "name": "Dev.to",
    "slug": "dev-to",
    "url": "https://dev.to/sandeep-oracle/oracle-sql-pseudo-columns-381o"
  },
  "original_language": "en",
  "account": "Oracle SQL pseudo-columns function like regular table columns but do not store data physically on disk. They are useful for administrative, navigational, and sequence-based queries. Key pseudo-columns include ROWID, ROWNUM, NEXTVAL, CURRVAL, COLUMN_VALUE, ORA_ROWSCN, and UID and USER.\n\nROWID provides a unique physical address for a row, while ROWNUM assigns a sequential integer to each row returned by a query. NEXTVAL and CURRVAL retrieve values from sequence objects. COLUMN_VALUE is used for collection types or table functions, ORA_ROWSCN returns the conservative upper bound System Change Number (SCN) of the most recent change, and UID and USER return the current user ID and username.\n\nPseudo-columns are assigned after WHERE clause evaluation but before ORDER BY and GROUP BY. For hierarchical queries, CONNECT_BY pseudo-columns like CONNECT_BY_ISLEAF, CONNECT_BY_ISCYCLE, and SYS_CONNECT_BY_PATH are used to organize nodes into a tree structure. These pseudo-columns help inspect tree structures and manage loops.\n\nPseudo-columns cannot be created or indexed directly, but virtual columns, introduced in Oracle 11g, allow custom expression-based columns that can be indexed. Virtual columns differ from pseudo-columns as they are stored in the table metadata and can be physically part of the table.",
  "summary": "1. Overview & Core Concepts Definition: A pseudo-column behaves like a table column, but it is not actually stored on disk in the table. Capabilities & Restrictions: You can SELECT from pseudo-columns, but you cannot perform INSERT , UPDATE , or DELETE operations on their values. 2. Common Oracle Pseudo-Columns Oracle provides several built-in pseudo-columns for administrative, navigational, and…",
  "key_points": [
    "Pseudo-columns behave like regular columns but don't store data physically.",
    "ROWID, ROWNUM, NEXTVAL, CURRVAL, COLUMNVALUE, ORAROWSCN, UID, and USER are key pseudo-columns.",
    "Pseudo-columns are evaluated after WHERE clause but before ORDER BY and GROUP BY."
  ],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}