The actual colors to be used are configured using the environment variable PG_COLORS (note plural). The value is a colon-separated list of key=value pairs. The keys specify what the color is to be used for. The values are SGR (Select Graphic Rendition) specifications, which are interpreted by the terminal.
The following keys are currently in use:
error
used to highlight the text “error” in error messages
warning
used to highlight the text “warning” in warning messages
locus
used to highlight location information (e.g., program name and file name) in messages
The default value is error=01;31:warning=01;35:locus=01 (01;31 = bold red, 01;35 = bold magenta, 01 = bold default color).
此色彩規範格式也廣為其他軟體套件所使用，例如 GCC，GNU coreutils 和 GNU grep。
PostgreSQL 中的大多數工具都可以產生彩色的輸出內容。本附錄描述了它的設定方式。
To use colorized output, set the environment variable PG_COLOR as follows:
If the value is always, then color is used.
If the value is auto and the standard error stream is associated with a terminal device, then color is used.
Otherwise, color is not used.