Functions and Operators

Operators can be used to process one or more operands and can be placed before, after, or between operands. Results are returned after the processing.

Functions encapsulate service logic to implement specific functions. A function may or may not have parameters. After a function is executed, the result is returned.

Users can modify system functions. However, after the modification, the meaning of the functions may change, which results in disorder in system control. Therefore, users are not allowed to manually modify system functions.

When the GUC parameter behavior_compat_options contains the 'enable_funcname_with_argsname' option, the projection alias displays the complete function.

• Logical Operators
  
• Comparison Operators
  
• Character Processing Functions and Operators
  
• Binary String Functions and Operators
  
• Bit String Functions and Operators
  
• Pattern Matching Operators
  
• Arithmetic Functions and Operators
  
• Date and Time Processing Functions and Operators
  
• Type Conversion Functions
  
• Geometric Functions and Operators
  
• Network Address Functions and Operators
  
• Text Search Functions and Operators
  
• JSON/JSONB Functions and Operators
  
• HLL Functions and Operators
  
• SEQUENCE Functions
  
• Array Functions and Operators
  
• Range Functions and Operators
  
• Aggregate Functions
  
• Window Functions
  
• Security Functions
  
• Encrypted Functions and Operators
  
• Set Returning Functions
  
• Conditional Expression Functions
  
• System Information Functions
  
• System Administration Functions
  
• Statistics Information Functions
  
• Trigger Functions
  
• Hash Function
  
• Prompt Message Function
  
• Fault Injection System Function
  
• Redistribution Parameters
  
• Distribution Key Recommendation Functions
  
• Other System Functions
  
• Internal Functions
  
• AI Feature Functions
  
• Dynamic Data Masking Functions
  
• Hotkey Feature Functions
  
• Global SysCache Functions
  
• Data Damage Detection and Repair Functions
  
• Functions of the XML Type
  
• Functions of the XMLType Type
  
• Obsolete Functions