Initial commit - Church Music Database

new-site/backend/utils/queryBuilder.js

@@ -0,0 +1,46 @@
+/**
+ * SQL Query Builder Utilities
+ */
+
+/**
+ * Build dynamic WHERE clause from conditions
+ * @param {Array} conditions - Array of SQL conditions
+ * @returns {string} WHERE clause or empty string
+ */
+const buildWhereClause = (conditions) => {
+  return conditions.length > 0 ? ` WHERE ${conditions.join(" AND ")}` : "";
+};
+
+/**
+ * Build LIMIT/OFFSET clause
+ * @param {number} limit - Max results
+ * @param {number} offset - Results to skip
+ * @param {number} paramOffset - Current parameter index
+ * @returns {Object} { clause, params }
+ */
+const buildPagination = (limit, offset, paramOffset = 1) => {
+  return {
+    clause: ` LIMIT $${paramOffset} OFFSET $${paramOffset + 1}`,
+    params: [parseInt(limit) || 100, parseInt(offset) || 0],
+  };
+};
+
+/**
+ * Build search condition for multiple fields
+ * @param {string} searchTerm - Search term
+ * @param {Array} fields - Fields to search in
+ * @param {number} paramIndex - Parameter index
+ * @returns {string} SQL condition
+ */
+const buildSearchCondition = (searchTerm, fields, paramIndex) => {
+  const conditions = fields.map(
+    (field) => `LOWER(${field}) LIKE $${paramIndex}`,
+  );
+  return `(${conditions.join(" OR ")})`;
+};
+
+module.exports = {
+  buildWhereClause,
+  buildPagination,
+  buildSearchCondition,
+};