diff --git a/lib/mysql-analyzer.sh b/lib/mysql-analyzer.sh
index 68008b6..20ba9ca 100755
--- a/lib/mysql-analyzer.sh
+++ b/lib/mysql-analyzer.sh
@@ -297,6 +297,7 @@ extract_database_from_query() {
 
 # Extract tables from query
 extract_tables_from_query() {
+    [ -z "$1" ] && return 1
     local query="$1"
 
     # Extract FROM and JOIN clauses
@@ -305,6 +306,7 @@ extract_tables_from_query() {
 
 # Analyze query performance with EXPLAIN
 explain_query() {
+    [ -z "$1" ] || [ -z "$2" ] && return 1
     local db_name="$1"
     local query="$2"
     local explain_file="${TEMP_SESSION_DIR}/explain_${db_name}_$$.tmp"
@@ -332,6 +334,7 @@ explain_query() {
 
 # Analyze queries and identify problems
 analyze_queries_for_problems() {
+    [ -z "$1" ] && return 1
     local query_file="$1"
     local problems_file="${TEMP_SESSION_DIR}/query_problems.tmp"
 
@@ -393,6 +396,7 @@ analyze_queries_for_problems() {
 
 # Generate plugin query statistics
 generate_plugin_statistics() {
+    [ -z "$1" ] && return 1
     local problems_file="$1"
     local stats_file="${TEMP_SESSION_DIR}/plugin_stats.tmp"
 
@@ -425,6 +429,7 @@ find_largest_tables() {
 
 # Check for bloated tables
 check_table_bloat() {
+    [ -z "$1" ] || [ -z "$2" ] && return 1
     local db_name="$1"
     local table_name="$2"
 
@@ -450,6 +455,7 @@ check_table_bloat() {
 
 # Recommend fixes for common issues
 recommend_fix() {
+    [ -z "$1" ] && return 1
     local issue="$1"
     local db_name="$2"
     local table_name="$3"
@@ -493,6 +499,7 @@ recommend_fix() {
 #############################################################################
 
 generate_summary_report() {
+    [ -z "$1" ] && return 1
     local problems_file="$1"
 
     print_banner "MySQL Query Analysis Summary"