Your data warehouse is expanding rapidly. How can you ensure optimal query performance as it grows?

To ensure optimal query performance as your data warehouse grows: 1. Proper indexing speeds up query retrieval. 2. Break large tables into smaller, manageable parts for faster access. 3. Regularly review and improve query efficiency by eliminating unnecessary joins or filtering early. 4. Cache frequently accessed data to reduce load times. 5. Use cloud scaling options to add resources as needed. 6. Continuously track performance and adjust configurations to keep queries running smoothly.

Kinh nghi?m trong các d? án t?i ?u c?a t?i: vi?c ?ánh index quan trong nh?t là làm sao l?a ch?n s? l??ng Index t?i thi?u nh?ng mang l?i hi?u qu? v?i l?n nh?t. Vi?c này quan tr?ng ? ch? s? l?a ch?n các t? h?p theo th? t? nào trong các composite index. Ví d? Index trên c?t (A,B,C) hay là Index trên (A, C,B) s? hoàn toàn khác nhau.

When we want to index a table, the first step is to identify the columns that are frequently used in WHERE conditions. This identification process hinges on thoroughly understanding the business requirements, as these requirements guide us in deciding whether to index a single column or create a composite index involving multiple columns based on the retrieval queries from the applications. Proper indexing can significantly reduce the time required to scan the entire table when retrieving data, thereby improving query performance. Additionally, it's important to periodically review and adjust indexes as business requirements evolve to ensure continued optimization of database performance.

Khuy?n cáo các h? th?ng l?n ??u nên thi?t k? Partition ngay t? ??u tiên - Các table có dung l??ng > 2GB ho?c s? l??ng b?n ghi h?n 10 tri?u ??u nên ngh? t?i gi?i pháp áp d?ng partitition. - Khi partition quan tr?ng là ph?i ch?n ?úng partition key, n?u kh?ng thì hi?u n?ng kh?ng t?ng mà có th? gi?m ?i - Partition nên k?t h?p cùng chi?n l??c vòng ??i d? li?u

Partitioning is a game changer when dealing with tables containing large volumes of records. It is an efficient method for optimizing query performance due to its structure. Partitioning works by breaking down a large table into smaller, more manageable sub-tables (partitions). This division is typically based on a specific column condition, such as the transaction date. For instance, when querying transactions from this year, the system will not scan the entire table but will instead directly access the partition containing the relevant data for this year, thereby speeding up retrieval times. Additionally, partitioning simplifies the archiving process, as you can easily detach partitions containing older data that is no longer needed.

Here are some tips for efficient Query Design: 1.Avoid SELECT *: Retrieve only the necessary columns to reduce data processing and improve performance. 2.Limit Rows: Use LIMIT or similar clauses to restrict the number of rows returned, especially for large datasets. 3.Indexed Columns: In WHERE and JOIN clauses, use indexed columns. For composite indexes, follow the column order in the index within WHERE conditions. 4.Subqueries: Use subqueries sparingly; avoid nested ones that hinder performance. Prefer CTEs or joins. 5.UNION ALL: Use UNION ALL instead of UNION for faster results, as it doesn't remove duplicates. 6.Batch Updates: Batch updates reduce the number of transaction commits. 7.Avoid Cursors: Cursors are slow in data processing.

Choose SELECT Fields over SELECT* Avoid SELECT DISTINCT Statements Define Filters Using WHERE Instead of HAVING Use Wildcards at the End of Phrases Use LIMIT to Sample Query Results Use INNER JOIN Instead of WHERE for joins CloudMiner( CM) is a fast and powerful GUI based Oracle Cloud query tool Row Mode Execution is a query processing method used with traditional RDBMS tables.It is very efficient for OLTP scenarios Batch Mode Execution is very efficient in Data Warehousing scenarios where large amounts of data are read and aggregated Using parantheses even when they are not required can improve readability of queries The Query Optimizer is one of the most important components of the Database Engine