Update README.md

Author: datsom1

README.md

@@ -141,14 +141,18 @@ If the columns in the CSV have changed, those added or removed columns will be i
       Compare the differences between two CSV or JSON files to find differences.
 
     Options:
-      --format TEXT      Explicitly specify input format. Available (csv|tsv|json) [default: auto-detect based on file extension]
-      --encoding TEXT    Input File Encoding. Available: (utf-8|utf-16|utf-16le|utf-16be|latin1|cp1252|ascii|...) [default: utf-8]
-      --key TEXT         Column to use as a unique ID for each row (ex: --key=Id) [default: first column if not specified] 
-      --output TEXT      Output format. Available: (readable|json|jsonfile)  [default: readable]
-      --outputfile FILE  File to write JSON output to (only used with --output=jsonfile)
-      --showunchanged    If a record is changed, show ALL fields, not just the changed fields.
-      --time             Measure and display elapsed time for the diff operation
-      --version          Show the version and exit.
-      -h, --help         Show this message and exit.
+      --key TEXT               Column to use as a unique ID for each row (ex: --key=Id). [default: first column header]
+      --output TEXT            Output format. Available: (readable|json|jsonfile). [default: readable]
+      --outfilename FILE       File to write JSON output to (only used with --output=jsonfile). [default: YYYY-MM-DD_HH-MM-SS_diffs.json]
+      --outfilepath DIRECTORY  Directory to save the output file (only used with --output=jsonfile). [default: current directory]
+      --fields TEXT            Comma-separated list of fields to compare (all others ignored). Mutually exclusive with --ignorefields. (example: --fields=Id,Name,Age__c,Email__c).
+      --ignorefields TEXT      Comma-separated list of fields to ignore during comparison. Mutually exclusive with --fields. (example: --ignorefields=LastModifiedDate,SystemModstamp,Days_Since_Last_Contact__c).
+      --showunchanged          If a record is changed, show ALL fields, not just the changed fields.
+      --time                   Measure and display elapsed time for the diff operation.
+      --format TEXT            Explicitly specify input format. Available (csv|tsv|json). [default: auto-detect based on file extension]
+      --encoding TEXT          Input File Encoding. Available: (utf-8|utf-16|utf-16le|utf-16be|latin1|cp1252|ascii|...).  [default: utf-8]
+      --streaming              Use streaming mode for very large CSV/TSV files (requires files to be sorted by key).
+      --version                Show the version and exit.
+      -h, --help               Show this message and exit.
 
-      Example: db-diff old.csv new.csv --key=Id --output=jsonfile --outputfile=diff.json
+      Example: db-diff old.csv new.csv --key=Id --output=jsonfile --outfilename=diff.json