Move check for binary mode and on_error option to the appropriate location.

Commit 9e2d870 placed the check for binary mode and on_error
before default values were inserted, which was not ideal.
This commit moves the check to a more appropriate position
after default values are set.

Additionally, the comment incorrectly mentioned two checks before
inserting defaults, when there are actually three. This commit corrects
that comment.

Author: Atsushi Torikoshi
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/8830518a-28ac-43a2-8a11-1676d9a3cdf8@oss.nttdata.com

Author: MasaoFujii

src/backend/commands/copy.c

@@ -672,7 +672,7 @@ ProcessCopyOptions(ParseState *pstate,
 	}
 
 	/*
-	 * Check for incompatible options (must do these two before inserting
+	 * Check for incompatible options (must do these three before inserting
 	 * defaults)
 	 */
 	if (opts_out->binary && opts_out->delim)
@@ -691,11 +691,6 @@ ProcessCopyOptions(ParseState *pstate,
 				(errcode(ERRCODE_SYNTAX_ERROR),
 				 errmsg("cannot specify %s in BINARY mode", "DEFAULT")));
 
-	if (opts_out->binary && opts_out->on_error != COPY_ON_ERROR_STOP)
-		ereport(ERROR,
-				(errcode(ERRCODE_SYNTAX_ERROR),
-				 errmsg("only ON_ERROR STOP is allowed in BINARY mode")));
-
 	/* Set defaults for omitted options */
 	if (!opts_out->delim)
 		opts_out->delim = opts_out->csv_mode ? "," : "\t";
@@ -900,6 +895,11 @@ ProcessCopyOptions(ParseState *pstate,
 					 errmsg("NULL specification and DEFAULT specification cannot be the same")));
 	}
 	/* Check on_error */
+	if (opts_out->binary && opts_out->on_error != COPY_ON_ERROR_STOP)
+		ereport(ERROR,
+				(errcode(ERRCODE_SYNTAX_ERROR),
+				 errmsg("only ON_ERROR STOP is allowed in BINARY mode")));
+
 	if (opts_out->reject_limit && !opts_out->on_error)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),