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How do you automate SQL queries in Oracle SQL Developer?

Schedule SQL Scripts Using SQL Developer

  1. Creating Credentials for Database Host and Database. A credential is an Oracle Scheduler object that has a user name and password pair stored in a dedicated database object.
  2. Defining Scheduler Job using Job Wizard. The Job wizard allows you to create a job schedule, using which you can define a workflow job.

How do I create an Oracle SQL query from a CSV file?

Steps to export query results to CSV in Oracle SQL Developer

  1. Step 1: Run your query. Firstly, you’ll need to run your query in SQL Developer.
  2. Step 2: Open the Export Wizard.
  3. Step 3: Select the CSV format and the location to export your file.
  4. Step 4: Export query results to CSV.

Can you run multiple SQL queries at once?

You can concatenate these queries in a string and execute that string. Another way is this solution. Simply put three queries one after the other in a . sql file, with semi-colons after each statement, then execute it as a script (either on a SQL*Plus prompt using @scriptname

How many table we can join in SQL?

Theoretically, there is no upper limit on the number of tables that can be joined using a SELECT statement. (One join condition always combines two tables!) However, the Database Engine has an implementation restriction: the maximum number of tables that can be joined in a SELECT statement is 64

How do I create a parallel query in SQL?

To achieve parallelism for SQL DML statements, you must first enable parallel DML in your session: ALTER SESSION ENABLE PARALLEL DML; Then any DML issued against a table with a parallel attribute will occur in parallel, if no PDML restrictions are violated.

How do I create a parallel query in Oracle?

To execute a query in parallel, Oracle Database generally creates a set of producer parallel execution servers and a set of consumer parallel execution servers. The producer server retrieves rows from tables and the consumer server performs operations such as join, sort, DML, and DDL on these rows.

What is full hint in Oracle?

Answer: The full hint is an optimizer directive used to force a full table scan of the specified table. The full hint should only be used to correct an optimizer error, in this case, when the optimizer chooses an index scan instead of a full-table scan.

What are Oracle SQL hints?

Hints let you make decisions usually made by the optimizer. As an application designer, you might know information about your data that the optimizer does not know. Hints provide a mechanism to direct the optimizer to choose a certain query execution plan based on the specific criteria.

How do I use parallel hints in Oracle?

SELECT /*+ PARALLEL(table_alias,Degree of Parallelism) */ FROM table_name table_alias; Let’s say a query takes 100 seconds to execute without using parallel hint. If we change DOP to 2 for same query, then ideally the same query with parallel hint will take 50 second. Similarly using DOP as 4 will take 25 seconds.

What is All_rows hint in Oracle?

ALL_ROWS. The ALL_ROWS hint explicitly chooses the cost-based approach to optimize throughput, that is, minimum total resource consumption. Results will be returned only after all processing has been completed.

What is a query hint?

Hints are options or strategies specified for enforcement by the SQL Server query processor on SELECT, INSERT, UPDATE, or DELETE statements. The hints override any execution plan the query optimizer might select for a query

Can we avoid index by using hint?

Table Hints. Suppose you want to use a specific index for your query to avoid a table scan, we can use table hints. One of the popular table hints is WITH(NOLOCK) to avoid default transaction isolation level and avoid locking issues in Select statements

What is Use_nl hint in Oracle?

About USE_NL, Oracle says: The USE_NL hint instructs the optimizer to join each specified table to another row source with a nested loops join, using the specified table as the inner table. The LEADING hint instructs the optimizer to use the specified set of tables as the prefix in the execution plan

How do I find Maxdop in SQL Server?

Using SQL Server Management Studio

  1. In Object Explorer, right-click a server and select Properties.
  2. Click the Advanced node.
  3. In the Max Degree of Parallelism box, select the maximum number of processors to use in parallel plan execution.

What does Maxdop 0 mean?

Max Degree of Parallelism

What should Maxdop be set to?

What is the Effective MAXDOP Setting? MAXDOP can be set to a value ranging between 0 and 32,767. The value tells SQL Server how many processors it should use for parallel plan execution. The default MAXDOP setting of 0 tells SQL Server to use all available processors (up to a max of 64)

Does changing Maxdop require restart?

1 Answer. Both of those server configuration options do not require a restart of the database engine. Running RECONFIGURE will be sufficient in this case.

How many NUMA nodes do I have?

Right click on the instance in the object explorer and select the CPU tab. Expand the “ALL” option. However many NUMA nodes are shown is the number of NUMA nodes that you have as shown below. You can even expand each NUMA nodes to see which logical processors are in each NUMA node

Do I need to restart SQL Server after changing Max memory?

Changing SQL Server’s Max Server memory is an online option – you don’t need to restart SQL Server. Though when you do make the change, you can and likely will cause data or procs to leave their caches so things could be a slight bit slower for a short while after you run it

What is NUMA in SQL Server?

NUMA stands for Non-Uniform Memory Access. The purpose of NUMA is for Scheduler (CPU) to have faster access to memory. Each CPU talks to memory controller to get the memory. When there are more than 8 CPUs, single memory controller becomes bottleneck