Query settings

16. Query Settings

When to Use

When tuning the underlying database query for performance, distinct results, or query debugging.

Query Configuration

SQL Query Options

query:
  type: views_query  # Standard SQL query
  options:
    query_comment: ''  # Comment added to SQL query
    disable_sql_rewrite: false  # Bypass node access query rewrite
    distinct: false  # SELECT DISTINCT
    replica: false  # Use replica database
    query_tags: []  # Tags for query altering (hook_query_TAG_alter)

Reference: core/modules/comment/config/optional/views.view.comment.yml lines 829-836

Options Explained

Option	Type	Purpose
`query_comment`	string	Adds comment to SQL for debugging/tracking
`disable_sql_rewrite`	boolean	DANGEROUS: Bypasses node access grants. Never use in production user-facing views.
`distinct`	boolean	Removes duplicate rows (useful with multiple relationships)
`replica`	boolean	Query replica database (if configured) for read-only queries
`query_tags`	sequence	Tags for `hook_query_TAG_alter()` — allows modules to modify query

Decision

If you need...	Use...	Why
Eliminate duplicate rows from relationships	`distinct: true`	Multiple relationships can cause row multiplication
Debug slow queries	`query_comment`	Identifies Views query in slow query log
Offload read traffic	`replica: true`	Uses replica database, reduces main DB load
Allow custom query modifications	`query_tags`	Hook alter system for contrib/custom modules
Bypass access checks (testing ONLY)	`disable_sql_rewrite: true`	Only for admin/testing views

Pattern

Query with distinct and debugging:

query:
  type: views_query
  options:
    query_comment: 'Articles view - main listing'
    disable_sql_rewrite: false
    distinct: true
    replica: false
    query_tags:
      - 'custom_module_alter'

DISTINCT and Relationships

When using multiple relationships, rows can multiply:

Without DISTINCT:

Node 1 → Tag A → Result row 1
Node 1 → Tag B → Result row 2
Node 2 → Tag A → Result row 3

Result: Node 1 appears twice.

With DISTINCT:

Node 1 → Result row 1 (tags aggregated or ignored)
Node 2 → Result row 2

Trade-off: DISTINCT slows query performance. Only use when necessary.

disable_sql_rewrite Security Warning

Setting disable_sql_rewrite: true bypasses all node access grants. This means: - Users can see unpublished content - Content access modules are ignored - Private content becomes visible

Only use for: - Admin-only views with strict access control - Migration/development debugging - Never for user-facing views

Common Mistakes

Using distinct: true without relationships → Unnecessary performance cost; DISTINCT only needed when relationships cause duplicates
Setting disable_sql_rewrite: true on user-facing views → CRITICAL SECURITY ISSUE; exposes private content
Empty query_comment on complex views → Hard to debug slow queries; always add descriptive comment for production views
Using replica: true on write-heavy views → Replica lag can show stale data; only use on read-only views
Adding query_tags without implementing alter hook → Tags do nothing unless module implements hook_query_TAG_alter()