SQL: Tips and Tricks

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Forgetting your MySQL root password can be scary, but thankfully there is a way to reset it. In this brief article, we will show you how.
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In our Introduction to PHP course, students create a poetry website. For the manual, I needed to create an ER diagram for the MySQL database on a Mac. I found the following options, both of which are free:
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In SQL, you round up to the nearest integer using the
CEIL
orCEILING
function, depending on whether you're using SQL Server, Oracle, MySQL or PostgreSQL. - Read Article
SQL Server, Oracle, MySQL and PostgreSQL each have their own way of doing string concatenation.
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You might wish to select all the columns in each row of a table in your SQL select statement. The syntax for accomplishing this task is straightforward because it does not require itemizing each column defined for the table.
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A select statement in SQL may contain one or more conditions (also known as predicates) in the where clause. A condition evaluates to true or false or unknown. The where clause must return a true value for a particular row to be selected.
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You must use at least one white space character between each keyword, table or column name in an SQL select. In addition, a semicolon is required as the statement delimiter.
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When you run a select statement the records, or rows, that are displayed are not guaranteed to be in a specific order. Usually, you will want to sort the records to make the report more meaningful. You will learn how to sort records in this topic.
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A subquery is select statement contained within an outer select statement. Two types of subqueries are available in SQL: the simple subquery and the correlated subquery. In this topic you will learn how to write each type of subquery.