Describe sql w3schools

SQL is a standard language for storing, manipulating and retrieving data in databases. HTML CSS JAVASCRIPT SQL PYTHON PHP BOOTSTRAP HOW TO W3. Provides a decription of the specified table or view.

For a list of tables in the current schema, use the Show Tables command. SQL DESC Statement ( Describe Table) SQL DESC statement use for describe the list of column definitions for specified table. You can use either DESC or DESCRIBE statement. Prerequisite : Sql Create Clause, As the name suggests, DESCRIBE is used to describe something. Since in database we have tables, that’s why we use DESCRIBE or DESC(both are same) command to describe the structure of a table.

The DESCRIBE and EXPLAIN statements are synonyms, used either to obtain information about table structure or query execution plans. For more information, see Section. Lists the column definitions for the specified table, view or synonym, or the specifications for the specified function or procedure. Represents the schema where the object resides.

Structured Query Language and Microsoft is not the only sql. The first is using DESCRIBE and the second by querying the INFORMATION_SCHEMA. MySQL What is DDL, DML and DCL? Here are described in detail.

By default, DESCRIBE displays information about all columns in the table. In this case, the statement displays information only for the named column. It can contain the SQL and _ wildcard characters. Which query will give the table structure with column definitions in SQL ? It depends from the database you use.

It is particularly useful in handling structured data, i. SQL - Indexes - Indexes are special lookup tables that the database search engine can use to speed up data retrieval. Simply put, an index is a pointer to data in a table. The DUAL is special one row, one column table present by default in all Oracle databases.

The owner of DUAL is SYS (SYS owns the data dictionary, therefore DUAL is part of the data dictionary.) but DUAL can be accessed by every user. A sequence is a user defined schema bound object that generates a sequence of numeric values. DESC VIEW and DESCRIBE TABLE are interchangeable. Either command retrieves the details for the table or view that matches the criteria in the statement.

To post-process the output of this comman you can use the RESULT_SCAN function, which treats the output as a table that can be queried. Allows users to describe the data. Basically, it is a set of sql statements that accept only input parameters, perform actions and return the result.

We can’t use a function to Insert, Update, Delete records in the database table(s). This SQL tutorial explains how to use the SQL INTERSECT operator with syntax and examples. However, it only returns the rows selected by all queries. A stored procedure is nothing more than prepared SQL code that you save so you can reuse the code over and over again. SQL Server Functions can return an only single value or a table.

In the previous tutorial, you learned how to delete data from multiple related tables using a single DELETE statement. Listing stored procedures – provide you with some useful commands to list stored procedures from databases. Use Data Columns to Describe Returned Events.

SQL Trace uses data columns in the trace output to describe events that are returned when the trace runs. HTML (Hypertext Markup Language) is the only markup language for creating web pages. Constraints are used to limit the type of data that can go into a table.

This means that it is designed to execute its work in all-or-nothing runs. The database engine is optimized to work in this manner an in general, it is more than sufficient to execute simple all-in-one type transactions. There are two types of functions in Oracle. Single Row Functions: Single row or Scalar functions return a value for every row that is processed in a query. Group Functions: These functions group the rows of data based on the values returned by the query.

This is discussed in SQL GROUP Functions. SQL is an ANSI and ISO standar and is the de facto standard database query language.