What SQL skills are required for a job?

Answer 1

Depends by your career roadmap.
SQL is used by software developers, data warehouse developers, reporting operators and database administrators.
Software Developers use a subset of SQL for to make simple operational transaction (select, insert, update and delete). Sometimes need to create query with than 3 join.
Data Warehouse developers use very complex SQL transactions for extract data from different data bases an a lot of table and load/update special tables called Datamart. Need to understand how the joins work on the engine of the data base for performance issue.
Reporting operators use organized database with clear table for extract a set of data for create fast reports. Need to know how aggregate information.
Database administrators support the Data Analyst for define the tables, views and relations between the tables for create and manage the entire data base. Need to know the subset of the SQL for to manage the tables and supervision the physical limit (hard disk space, cpu time, network limits...).

Answer 2

sql is just a query language, you just need 3 hours maximum to know sql to its best.
You must know how to generate the required results from any database by using queries.

Answer 3

DDL , DML, DCL , TCL commands, character functions, set operators, logical operators, joins , subquery , constraints .....these are important concepts for interview.

Answer 4

SQL Skills is very required in indonesia. in the new startup Corporation. like Tokopedia or bukalapak.

Answer 5

Claudio Antonelli good answer, the best.

Answer 6

you need just understanding of all the queries well, like DDL,DML,DCL,TCl.. if you gt this all queries clearly your done to do that all things. do best.