Document the ISNUMERIC function.
diff --git a/_docs/en/sql-reference/sql-functions/021-data-type-functions.md b/_docs/en/sql-reference/sql-functions/021-data-type-functions.md
index a9597fe..4a6da18 100644
--- a/_docs/en/sql-reference/sql-functions/021-data-type-functions.md
+++ b/_docs/en/sql-reference/sql-functions/021-data-type-functions.md
@@ -8,18 +8,18 @@
Drill supports the following functions that return data type information:
-**sqlTypeOf()**
-Returns the data type of a column (using the SQL names) whether the column is NULL or not. You can use the SQL name in a CAST statement, for example:
-
- sqlTypeOf( CAST(x AS <data type> ))
- //Returns <data type> as the type name.
-If the type is DECIMAL, the type also includes precision and scale, for example:
-
- DECIMAL(6, 3)
-**modeOf()**
-Returns the cardinality (mode) of the column as "NOT NULL", "NULLABLE", or "ARRAY". Drill data types include a cardinality, for example `Optional Int` or `Required VarChar`.
-
-**drillTypeOf()**
+**sqlTypeOf()**
+Returns the data type of a column (using the SQL names) whether the column is NULL or not. You can use the SQL name in a CAST statement, for example:
+
+ sqlTypeOf( CAST(x AS <data type> ))
+ //Returns <data type> as the type name.
+If the type is DECIMAL, the type also includes precision and scale, for example:
+
+ DECIMAL(6, 3)
+**modeOf()**
+Returns the cardinality (mode) of the column as "NOT NULL", "NULLABLE", or "ARRAY". Drill data types include a cardinality, for example `Optional Int` or `Required VarChar`.
+
+**drillTypeOf()**
Similar to typeOf(), but returns the internal Drill names even if the value is NULL.
_____
diff --git a/_docs/en/sql-reference/sql-functions/040-string-manipulation.md b/_docs/en/sql-reference/sql-functions/040-string-manipulation.md
index 454a736..7a5d62a 100644
--- a/_docs/en/sql-reference/sql-functions/040-string-manipulation.md
+++ b/_docs/en/sql-reference/sql-functions/040-string-manipulation.md
@@ -13,6 +13,7 @@
| [CONCAT]({{ site.baseurl }}/docs/string-manipulation/#concat) | VARCHAR |
| [ILIKE]({{ site.baseurl }}/docs/string-manipulation/#ilike) | BOOLEAN |
| [INITCAP]({{ site.baseurl }}/docs/string-manipulation/#initcap) | VARCHAR |
+| [ISNUMERIC]({{ site.baseurl }}/docs/string-manipulation/#isnumeric) | INTEGER |
| [LENGTH]({{ site.baseurl }}/docs/string-manipulation/#length) | INTEGER |
| [LIKE]({{ site.baseurl }}/docs/string-manipulation/#like) | BOOLEAN |
| [LOWER]({{ site.baseurl }}/docs/string-manipulation/#lower) | VARCHAR |
@@ -166,6 +167,23 @@
|--------------------------|
1 row selected (0.106 seconds)
+## ISNUMERIC
+Returns a 1 if the string argument matches the regular expression `[-+]?\d+(\.\d+)?` otherwise a 0.
+
+### ISNUMERIC Syntax
+
+ ISNUMERIC(string)
+
+### ISNUMERIC Examples
+
+ SELECT ISNUMERIC('3.1415926');
+ |--------|
+ | EXPR$0 |
+ |--------|
+ | 1 |
+ |--------|
+ 1 row selected (0.185 seconds)
+
## LENGTH
Returns the number of characters in the string.
