Add support for sqlite_math_functions tag (#1059)

Add support for SQLITE_ENABLE_MATH_FUNCTIONS compile-time option via the sqlite_math_functions build tag.

Co-authored-by: Dominik Kraus <dominik.kraus@nktek.de>

.github/workflows/go.yaml

@@ -44,7 +44,7 @@ jobs:
         run: go-acc . -- -race -v -tags "libsqlite3"
 
       - name: 'Tags: full'
-        run: go-acc . -- -race -v -tags "sqlite_allow_uri_authority sqlite_app_armor sqlite_foreign_keys sqlite_fts5 sqlite_icu sqlite_introspect sqlite_json sqlite_os_trace sqlite_preupdate_hook sqlite_secure_delete sqlite_see sqlite_stat4 sqlite_trace sqlite_userauth sqlite_vacuum_incr sqlite_vtable sqlite_unlock_notify sqlite_column_metadata"
+        run: go-acc . -- -race -v -tags "sqlite_allow_uri_authority sqlite_app_armor sqlite_column_metadata sqlite_foreign_keys sqlite_fts5 sqlite_icu sqlite_introspect sqlite_json sqlite_math_functions sqlite_os_trace sqlite_preupdate_hook sqlite_secure_delete sqlite_see sqlite_stat4 sqlite_trace sqlite_unlock_notify sqlite_userauth sqlite_vacuum_incr sqlite_vtable"
 
       - name: 'Tags: vacuum'
         run: go-acc . -- -race -v -tags "sqlite_vacuum_full"
@@ -99,7 +99,7 @@ jobs:
       - name: 'Tags: full'
         run: |
           echo 'skip this test'
-          echo go build -race -v -tags "sqlite_allow_uri_authority sqlite_app_armor sqlite_foreign_keys sqlite_fts5 sqlite_icu sqlite_introspect sqlite_json sqlite_preupdate_hook sqlite_secure_delete sqlite_see sqlite_stat4 sqlite_trace sqlite_userauth sqlite_vacuum_incr sqlite_vtable sqlite_unlock_notify"
+          echo go build -race -v -tags "sqlite_allow_uri_authority sqlite_app_armor sqlite_column_metadata sqlite_foreign_keys sqlite_fts5 sqlite_icu sqlite_introspect sqlite_json sqlite_math_functions sqlite_preupdate_hook sqlite_secure_delete sqlite_see sqlite_stat4 sqlite_trace sqlite_unlock_notify sqlite_userauth sqlite_vacuum_incr sqlite_vtable"
         shell: msys2 {0}
 
       - name: 'Tags: vacuum'

README.md

@@ -172,6 +172,7 @@ go build --tags "icu json1 fts5 secure_delete"
 |  International Components for Unicode | sqlite_icu | This option causes the International Components for Unicode or "ICU" extension to SQLite to be added to the build |
 | Introspect PRAGMAS | sqlite_introspect | This option adds some extra PRAGMA statements. <ul><li>PRAGMA function_list</li><li>PRAGMA module_list</li><li>PRAGMA pragma_list</li></ul> |
 | JSON SQL Functions | sqlite_json | When this option is defined in the amalgamation, the JSON SQL functions are added to the build automatically |
+| Math Functions | sqlite_math_functions | This compile-time option enables built-in scalar math functions. For more information see [Built-In Mathematical SQL Functions](https://www.sqlite.org/lang_mathfunc.html) |
 | OS Trace | sqlite_os_trace | This option enables OSTRACE() debug logging. This can be verbose and should not be used in production. |
 | Pre Update Hook | sqlite_preupdate_hook | Registers a callback function that is invoked prior to each INSERT, UPDATE, and DELETE operation on a database table. |
 | Secure Delete | sqlite_secure_delete | This compile-time option changes the default setting of the secure_delete pragma.<br><br>When this option is not used, secure_delete defaults to off. When this option is present, secure_delete defaults to on.<br><br>The secure_delete setting causes deleted content to be overwritten with zeros. There is a small performance penalty since additional I/O must occur.<br><br>On the other hand, secure_delete can prevent fragments of sensitive information from lingering in unused parts of the database file after it has been deleted. See the documentation on the secure_delete pragma for additional information |

sqlite3_opt_math_functions.go

@@ -0,0 +1,14 @@
+// Copyright (C) 2022 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build sqlite_math_functions
+
+package sqlite3
+
+/*
+#cgo CFLAGS: -DSQLITE_ENABLE_MATH_FUNCTIONS
+#cgo LDFLAGS: -lm
+*/
+import "C"

sqlite3_opt_math_functions_test.go

@@ -0,0 +1,29 @@
+// +build sqlite_math_functions
+
+package sqlite3
+
+import (
+	"database/sql"
+	"testing"
+)
+
+func TestMathFunctions(t *testing.T) {
+	db, err := sql.Open("sqlite3", ":memory:")
+	if err != nil {
+		t.Fatal("Failed to open database:", err)
+	}
+	defer db.Close()
+
+	queries := []string{
+		`SELECT acos(1)`,
+		`SELECT log(10, 100)`,
+		`SELECT power(2, 2)`,
+	}
+
+	for _, query := range queries {
+		var result float64
+		if err := db.QueryRow(query).Scan(&result); err != nil {
+			t.Errorf("invoking math function query %q: %v", query, err)
+		}
+	}
+}