# Argument Modes > Exact behavior of default, meta, taxonomy, date, ACF relationship, query bundle, and mapped bundle modes. # Argument Modes Argument mode decides what a facet value becomes in the backend query. Select, SearchSelect, Radio List, and Checkbox List share the `FacetQueryProperties` mode system. Search Facet implements the same mode names separately because text search needs partial-match aliases and multi-argument text bundling. ## Mode Summary | Mode | Runtime facet type | Used by | Value meaning | | --- | --- | --- | --- | | `default` | selected query argument, such as `category_name` or `post_type` | Search and option facets | The value is assigned to a standard WP query argument. | | `meta` | `meta_value` | Search and option facets | The value is compared against a configured post meta key. | | `tax` | `tax_query` for option facets, `tax_query_like` for Search Facet | Search and option facets | The value is interpreted as a term field for a configured taxonomy. | | `date` | `date_query` | Search and option facets | The value is interpreted as a date range for a configured post date column. | | `acf_relationship` | `acf_relationship` | Search and option facets | The value is a related post ID, or comma-separated IDs, matched against a serialized relationship meta field. | | multi-argument Search Facet | `query_bundle` | Search Facet only | One typed text value expands into multiple query clauses. | | multi-argument option facet | `mapped_bundle` | Select, SearchSelect, Radio List, Checkbox List | One authored option expands into multiple query clauses with per-option mapped values. | ## Default Query Argument Default mode writes a standard query argument. Option facets use values from `FacetQueryProperties`, including: ```text search, p, name, title, post_type, order, orderby, category_name, tag, author, author_name, year, monthnum, posts_per_page ``` Search Facet has a filter-oriented set and uses partial aliases for text fields: ```text search, p, title_like, name_like, post_type, category_name_like, tag_like, author, author_name_like, year, monthnum ``` Use default mode for common query arguments like post type, category slug, tag slug, author, year, month, ordering, and posts per page. ## Meta Argument Meta mode uses: - `meta_key` - `meta_compare` - `meta_type` Option facets default `meta_compare` to `=`, while Search Facet defaults it to `LIKE`. Supported compares are: ```text =, !=, >, >=, <, <=, LIKE, NOT LIKE, IN, NOT IN, BETWEEN, NOT BETWEEN, EXISTS, NOT EXISTS ``` Use comma-separated values for `IN`, `NOT IN`, `BETWEEN`, and `NOT BETWEEN`. E2E coverage verifies exact numeric matches, char matches, bool matches, range compares, substring compares, set compares, and values with spaces. ## Taxonomy Argument Tax mode uses: - `taxonomy` - `tax_field` Supported fields are: ```text slug, term_id, name, term_taxonomy_id ``` Option facets produce exact `tax_query` clauses. Search Facet produces `tax_query_like`, so it can search term names or slugs by typed text where supported by the backend clause handling. The taxonomy E2E scenario verifies `facet_color` with all four fields and also covers multiple taxonomy filters. ## Date Query Date mode uses a configured date column: ```text post_date, post_modified, post_date_gmt, post_modified_gmt ``` Authored option values should use: ```text YYYY-MM-DD,YYYY-MM-DD ``` The first date is the start, and the second is the end. Search Facet sends the typed input through the same `date_query` facet type. ## ACF Relationship ACF relationship mode uses `acf_relationship_argument.meta_key`, which is the relationship field stored on the posts being filtered. The value must be a numeric related post ID, or a comma-separated list of related post IDs. It does not reverse-resolve a bidirectional relationship stored only on the related posts. Example rule: ```text If you filter Events by Speaker, the Event posts must store the selected Speaker IDs in the configured relationship field. ``` The `wp_query_args` E2E scenario verifies select and checkbox ACF relationship filters, counts, unavailable state, comma-list option values, and direct URL hydration. ## Search Facet Query Bundle When `target_multiple_query_arguments` is enabled on Search Facet, the control renders as `query_bundle`. One typed search value is applied to every row in `query_argument_mappings`. The `query_argument_relation` setting controls whether the generated clauses are joined with `AND` or `OR`. Search mappings normalize common exact types to partial search aliases, for example `title` becomes `title_like` and `category_name` becomes `category_name_like`. Use this when one text field should search several places, such as title or priority, or title or category. ## Option Facet Mapped Bundle When `target_multiple_query_arguments` is enabled on Select, SearchSelect, Radio List, or Checkbox List, the root facet type becomes `mapped_bundle`. The parent facet defines `query_argument_mappings`. Each option defines `query_value_mappings`. At runtime, an option is valid only when its value mappings can be matched to the parent mapping keys. Example: ```text Parent mappings: - category -> default category_name - priority -> meta facet_priority Option "News + High priority": - category = facets-e2e-news - priority = high ``` The mapped bundle E2E coverage verifies filtering, URL restore, counts, unavailable state, and availability updates after other filters change.