Merge pull request #62 from mobley-trent/charidx

feat(string functions): CHARINDEX function
AmrDeveloper · Dec 20, 2023 · b446caa · b446caa
2 parents d2b6ced + 6db894c
commit b446caa
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diff --git a/crates/gitql-ast/src/function.rs b/crates/gitql-ast/src/function.rs
@@ -30,6 +30,7 @@ lazy_static! {
         map.insert("datalength", text_datalength);
         map.insert("char", text_char);
         map.insert("nchar", text_char);
+        map.insert("charindex", text_charindex);
         map.insert("replace", text_replace);
         map.insert("substring", text_substring);
         map.insert("stuff", text_stuff);
@@ -173,6 +174,13 @@ lazy_static! {
                 result: DataType::Text,
             },
         );
+        map.insert(
+            "charindex",
+            Prototype {
+                parameters: vec![DataType::Text, DataType::Text],
+                result: DataType::Integer,
+            }
+        );
         map.insert(
             "replace",
             Prototype {
@@ -478,6 +486,17 @@ fn text_char(inputs: Vec<Value>) -> Value {
     Value::Text("".to_string())
 }
 
+fn text_charindex(inputs: Vec<Value>) -> Value {
+    let substr = inputs[0].as_text();
+    let input = inputs[1].as_text();
+
+    if let Some(index) = input.to_lowercase().find(&substr.to_lowercase()) {
+        Value::Integer(index as i64 + 1)
+    } else {
+        Value::Integer(0)
+    }
+}
+
 fn text_replace(inputs: Vec<Value>) -> Value {
     let text = inputs[0].as_text();
     let old_string = inputs[1].as_text();

diff --git a/docs/function/functions.md b/docs/function/functions.md
@@ -18,6 +18,7 @@ note that all functions names are case-insensitive.
 | LEFT       | Text, Integer                | Text    | Extracts a number of characters from a string (starting from left).                                                                                                  |
 | DATALENGTH | Text                         | Integer | Returns the number of bytes used to represent an expression.                                                                                                         |
 | CHAR       | Integer                      | Text    | Returns the character based on the ASCII code.                                                                                                                       |
+| CHARINDEX  | Text, Text                   | Integer | Returns the starting position of the first occurrence of a string in another string.                                                                                 |
 | NCHAR      | Integer                      | Text    | Returns the character based on the ASCII code.                                                                                                                       |
 | REPLACE    | Text, Text, Text             | Text    | Replaces all occurrences of a substring within a string, with a new substring.                                                                                       |
 | SUBSTRING  | Text, Integer, Integer       | Text    | Extracts some characters from a string.                                                                                                                              |
@@ -41,6 +42,7 @@ SELECT name, ASCII(name) AS firstCharAscii FROM commits
 SELECT LEFT("AmrDeveloper", 3) AS extract
 SELECT DATALENGTH("AmrDeveloper") as bytelength
 SELECT CHAR(345) AS code
+SELECT CHARINDEX("DEV", "AmrDeveloper") AS position
 SELECT REPLACE("ABC ABC ABC", "a", "c") as replacedText
 SELECT name, SUBSTRING(name, 1, 5) AS extract FROM commits
 SELECT STUFF("GQL tutorial!", 13, 1, " is fun!")