How can you optimize fintech databases for mobile devices using SQL?

1 Use indexes wisely

Indexes are data structures that help you find and sort records in a table faster. They can speed up your queries by reducing the number of scans and comparisons needed to locate the data you want. However, indexes also have some drawbacks, such as taking up space, slowing down insertions and updates, and requiring maintenance. Therefore, you should use indexes wisely and only create them for the columns that you frequently use in your queries, especially those with high cardinality (unique values) and low selectivity (narrow range of values). You should also avoid indexing columns that are frequently modified or have large data types, such as text or blob.

2 Use joins carefully

Joins are operations that combine data from two or more tables based on a common column or condition. They can help you retrieve related data from different sources and perform complex calculations. However, joins can also be costly and time-consuming, especially if you join large tables or use inefficient join types. Therefore, you should use joins carefully and only when necessary. You should also follow some best practices, such as using inner joins instead of outer joins, using explicit join syntax instead of implicit join syntax, using join conditions that are indexed and have high selectivity, and limiting the number of tables you join in a single query.

3 Use subqueries sparingly

Subqueries are queries that are nested inside another query and return a single value, a set of values, or a table. They can help you simplify your queries, filter your data, and perform calculations. However, subqueries can also be expensive and complicated, especially if you use multiple or correlated subqueries. Therefore, you should use subqueries sparingly and only when they are more efficient than alternatives. You should also follow some best practices, such as using EXISTS or IN instead of NOT EXISTS or NOT IN, using subqueries in the WHERE clause instead of the SELECT clause, and avoiding subqueries that return large or unsorted data sets.

4 Use functions and procedures

Functions and procedures are blocks of code that perform specific tasks and can be reused in multiple queries. They can help you modularize your code, enhance your logic, and reduce duplication. However, functions and procedures can also introduce some overhead and complexity, especially if you use them incorrectly or excessively. Therefore, you should use functions and procedures wisely and only when they add value to your queries. You should also follow some best practices, such as using built-in functions instead of custom functions, using procedures instead of functions for complex or multiple operations, and avoiding functions or procedures that access the database or perform calculations on every row.

5 Use encryption and authentication

Encryption and authentication are techniques that protect your data from unauthorized access and modification. They can help you secure your fintech databases and comply with regulatory and ethical standards. However, encryption and authentication can also affect your query performance and usability, especially if you use them improperly or inconsistently. Therefore, you should use encryption and authentication appropriately and only when they are required. You should also follow some best practices, such as using encryption for sensitive or confidential data, using authentication for user or role-based access, and avoiding encryption or authentication that are too weak or too strong for your needs.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?