What is the use of describe command in SQL?
What is the use of describe command in SQL?
The DESCRIBE command enables you to describe objects recursively to the depth level set in the SET DESCRIBE command. You can also display the line number and indentation of the attribute or column name when an object contains multiple object types. For more information, see the SET command.
What does (+) mean in Oracle SQL?
outer join
The plus sign is Oracle syntax for an outer join. There isn’t a minus operator for joins. An outer join means return all rows from one table. Also return the rows from the outer joined where there’s a match on the join key. If there’s no matching row, return null.
How do you describe an object in SQL?
Simply put the cursor on a function, table, or other object in the editor window and press the F4 key, and detail about the object appears. The F4 or Describe window is useful for displaying object information and table information including data, syntax, and statistics.
How to do a SQL Plus command in Oracle?
SQL*Plus Commands. 1 Enter SQL*Plus commands to configure the SQL*Plus environment. 2 Startup and shutdown an Oracle database. 3 Connect to an Oracle database. 4 Enter and execute SQL commands and PL/SQL blocks. 5 Format and print query results.
What does the describe command do in Oracle?
The description for tables, views, types and synonyms contains the following information: When you do a DESCRIBE, VARCHAR columns are returned with a type of VARCHAR2. The DESCRIBE command enables you to describe objects recursively to the depth level set in the SET DESCRIBE command.
What do you need to know about SQL Plus?
SQL*Plus is a command-line tool that provides access to the Oracle RDBMS. SQL*Plus enables you to: Enter SQL*Plus commands to configure the SQL*Plus environment Startup and shutdown an Oracle database
How are command line commands used in SQL?
The SQL Command Line SET commands can be used to specify various SQL Command Line settings, such as the format of the output from SQL SELECT statements. For example, the following SET commands specify the number of lines for each page and the number of characters for each line in the output:
What is the use of describe command in SQL? The DESCRIBE command enables you to describe objects recursively to the depth level set in the SET DESCRIBE command. You can also display the line number and indentation of the attribute or column name when an object contains multiple object types. For more information, see the…