Created SC2071 (markdown)

SC2071.md

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+## > is for string comparisons. Use -gt instead.
+
+### Problematic code:
+
+```sh
+if [[ $var > 10 ]]
+then
+  echo "Triggers when var=5 and var=20"
+fi
+```
+
+### Correct code:
+
+```sh
+if [[ $var -gt 10 ]]
+then
+  echo "Correct numerical comparison"
+fi
+```
+### Rationale:
+
+`<` and `>`, in both `[[` and `[` (when escaped) will do a lexicographical comparison, not a numerical comparison. 
+
+This means that `[[ 5 > 10 ]]` is true because 5 comes after 10 alphabetically. Meanwhile `[[ 5 -gt 10 ]]` is false because 5 does not come after 10 numerically.
+
+If you want to compare numbers by value, use the numerical comparison operators `-gt`, `-ge`, `-lt` and `-le`.
+
+### Exceptions:
+
+None.