String Manipulation Functions¶ We use string manipulation functions quite extensively. Here are some of the important functions which we typically use. Case Conversion – lower, upper, initcap Getting size of the column value – length Extracting Data – substr and split_part Trimming and Padding functions – trim, rtrim, ltrim, rpad and lpad Reversing strings – …
Overview of Pre-Defined Functions¶ Like any RDBMS, Postgres provides robust set of pre-defined functions to come up with solutions quickly as per the business requirements. There are many functions, but we will see the most common ones here. Following are the categories of functions that are more commonly used. String Manipulation Date Manipulation Numeric Functions …
Pre-Defined Functions¶ Let us go through the pre-defined functions available in Postgresql. Overview of Pre-Defined Functions String Manipulation Functions Date Manipulation Functions Overview of Numeric Functions Data Type Conversion Handling Null Values Using CASE and WHEN Exercises – Pre-Defined Functions Here are the key objectives of this section. How to use official documentation of Postgres …
Dropping Tables¶ Let us go through the details related to dropping tables. We can drop table using DROP TABLE. All the direct dependent objects such as indexes, primary key constraints, unique constraints, not null constraints will automatically be dropped. Sequences will be dropped only if the sequence is owned by the column. If there are …
Truncating Tables¶ Let us understand details related to truncating tables. If you want to delete the data from a table entirely, then TRUNCATE is the fastest way to do so. Irrespective of size of the table, data can be cleaned up with in no time. Truncate operations can be rolled back. TRUNCATE is a DDL …
Overview of Sequences¶ Let us go through some of the important details related to sequences. For almost all the tables in relational databases we define primary key constraints. Primary key is nothing but unique constraint with not null and there can be only one primary key in any given table. Many times, we might not …
