Automatic database optimization and performance tweaks (#3527)

* Automatic database optimize
* Tweak connection pooling

pkg/sqlite/driver.go

@@ -0,0 +1,71 @@
+package sqlite
+
+import (
+	"database/sql"
+	"database/sql/driver"
+	"fmt"
+
+	"github.com/fvbommel/sortorder"
+	sqlite3 "github.com/mattn/go-sqlite3"
+)
+
+const sqlite3Driver = "sqlite3ex"
+
+func init() {
+	// register custom driver
+	sql.Register(sqlite3Driver, &CustomSQLiteDriver{})
+}
+
+type CustomSQLiteDriver struct{}
+
+type CustomSQLiteConn struct {
+	*sqlite3.SQLiteConn
+}
+
+func (d *CustomSQLiteDriver) Open(dsn string) (driver.Conn, error) {
+	sqlite3Driver := &sqlite3.SQLiteDriver{
+		ConnectHook: func(conn *sqlite3.SQLiteConn) error {
+			funcs := map[string]interface{}{
+				"regexp":            regexFn,
+				"durationToTinyInt": durationToTinyIntFn,
+				"basename":          basenameFn,
+			}
+
+			for name, fn := range funcs {
+				if err := conn.RegisterFunc(name, fn, true); err != nil {
+					return fmt.Errorf("error registering function %s: %v", name, err)
+				}
+			}
+
+			// COLLATE NATURAL_CS - Case sensitive natural sort
+			err := conn.RegisterCollation("NATURAL_CS", func(s string, s2 string) int {
+				if sortorder.NaturalLess(s, s2) {
+					return -1
+				} else {
+					return 1
+				}
+			})
+
+			if err != nil {
+				return fmt.Errorf("error registering natural sort collation: %v", err)
+			}
+
+			return nil
+		},
+	}
+
+	conn, err := sqlite3Driver.Open(dsn)
+	if err != nil {
+		return nil, err
+	}
+
+	return &CustomSQLiteConn{conn.(*sqlite3.SQLiteConn)}, nil
+}
+
+func (c *CustomSQLiteConn) Close() error {
+	conn := c.SQLiteConn
+
+	_, _ = conn.Exec("PRAGMA analysis_limit=1000; PRAGMA optimize;", []driver.Value{})
+
+	return conn.Close()
+}