Static SQL refers to those fixed SQL statements that can be hard-coded into the application. Since static SQL is a fixed query, these statements can be analyzed and optimized without any special handling for security purposes.
Dynamic SQL refers to SQL statements that do not exist. Dynamically generated and run within the application based on user input. Dynamic Sqls helps in developing versatile and flexible applications. Dynamic SQL may require additional permissions and security handling, and malicious users may create dangerous code.
The following are some important differences between static routing and dynamic routing.
advanced. no. | Key | Static SQL | Dynamic SQL |
---|---|---|---|
Database access | In static SQL, the database access process is predetermined in the statement. | In dynamic SQL, how to access the database can only be determined at runtime. | |
Efficiency | Static SQL statements are faster and more efficient. | Dynamic SQL statements are less efficient. | |
Compilation | Static SQL statements are compiled at compile time. | Dynamic SQL statements are compiled at runtime. | |
Application plan parsing, verification, optimization, and generation are compile-time activities. | Application plan parsing, verification, optimization, and generation are runtime activities. | ||
Use case | Static SQL is used when data is evenly distributed. | Dynamic SQL is used when data is non-uniformly distributed. | |
Dynamic statements | Do not use EXECUTE IMMEDIATE, EXECUTE, PREPARE and other statements. | Use EXECUTE IMMEDIATE, EXECUTE, PREPARE and other statements | |
Flexibility | Static SQL has poor flexibility. | Dynamic SQL has high flexibility. |
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