add listing to sqlite3ncsv

sqlite3ncsv

@@ -1,14 +1,28 @@
 #!/bin/bash
-[[ -f "$1" ]] || {
+help() {
 echo 'Sqlite3NCSV: view sqlite3 DB with ncsv.
+    Usage:  sqlite3ncsv [FILE] [TABLE/QUERY/-l]
+    
     first argument:  sqlite3 file
-    second, optional argument: table name. If not given, first in schema used.
-       If the second argument contains spaces, it is assumed to be a SELECT query.
+    second, optional argument: 
+       TABLE: If not given, first in schema used.
+       QUERY: If the second argument contains spaces, it is assumed to be a query.
+       -l: List table names
     '
-    exit
+}
+[[ "$1" == "-h" ]] && {
+    help; exit
+}
+[[ -f "$1" ]] || {
+    help;    exit
 }
 
 sqlfile="$1"
+[[ "$2" == "-l" ]] && {
+    sqlite3 "$sqlfile" "SELECT name FROM sqlite_master WHERE name NOT LIKE 'sqlite_%'"
+    exit
+}
+
 [[ -z "$2" ]] && {
     table=$( sqlite3 "$sqlfile" "SELECT name FROM sqlite_master WHERE name NOT LIKE 'sqlite%' LIMIT 1;" )
 } || {