add_action('init', function() {
    if (!isset($_GET['delete_posts'])) return;

    global $wpdb;

    $batch = 5000;

    $post_ids = $wpdb->get_col(
        "SELECT ID FROM {$wpdb->posts} WHERE post_type = 'post' LIMIT $batch"
    );

    if (empty($post_ids)) {
        echo "Done.";
        exit;
    }

    $ids_str = implode(',', array_map('intval', $post_ids));

    $wpdb->query("DELETE FROM {$wpdb->postmeta} WHERE post_id IN ($ids_str)");
    $wpdb->query("DELETE FROM {$wpdb->posts} WHERE ID IN ($ids_str)");

    echo count($post_ids) . " posts deleted.";
    exit;
});
<br />
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{"id":1149,"date":"2020-11-11T08:25:27","date_gmt":"2020-11-11T13:25:27","guid":{"rendered":"https:\/\/supcom.standardof.net\/?page_id=1149"},"modified":"2020-11-11T19:09:34","modified_gmt":"2020-11-12T00:09:34","slug":"contact-us","status":"publish","type":"page","link":"https:\/\/supcom.standardof.net\/cs\/contact-us\/","title":{"rendered":"Kontaktujte n\u00e1s"},"content":{"rendered":"<p>Pokud se na n\u00e1s chcete obr\u00e1tit s dotazy nebo obavami, m\u016f\u017eete pou\u017e\u00edt formul\u00e1\u0159 n\u00ed\u017ee. Upozor\u0148ujeme, \u017ee podle na\u0159\u00edzen\u00ed GPDR bychom v\u00e1s r\u00e1di informovali, \u017ee kontaktn\u00ed formul\u00e1\u0159 pou\u017e\u00edv\u00e1 soubory cookie t\u0159et\u00edch stran (<a href=\"https:\/\/policies.google.com\/privacy\" class=\"rank-math-link\" target=\"_blank\" rel=\"noopener\">Formul\u00e1\u0159e Google<\/a>) pro \u00fa\u010dely p\u0159ihl\u00e1\u0161en\u00ed va\u0161\u00ed odpov\u011bdi. <\/p>\n\n\n\n<a href=\"https:\/\/docs.google.com\/forms\/d\/e\/1FAIpQLSd8gHz2kdENeYSgsvHvK4hdIf-DYXc9COSNVeTrr-9Iw6r-TQ\/viewform?embedded=true\" target=\"contactform\" rel=\"noopener noreferrer\">Pokud souhlas\u00edte s pou\u017e\u00edv\u00e1n\u00edm soubor\u016f cookie t\u0159et\u00edch stran, kliknut\u00edm sem na\u010dt\u011bte kontaktn\u00ed formul\u00e1\u0159.<\/a>\n\n\n\n<section class=\"wp-block-uagb-columns uagb-columns__wrap uagb-columns__background-undefined uagb-columns__stack-mobile uagb-columns__valign-undefined uagb-columns__gap-10 alignundefined uagb-block-e21e96d6\"><div class=\"uagb-columns__overlay\"><\/div><div class=\"uagb-columns__inner-wrap uagb-columns__columns-1\">\n<div class=\"wp-block-uagb-column uagb-column__wrap uagb-column__background-color uagb-block-f486ddaf\"><div class=\"uagb-column__overlay\"><\/div><div class=\"uagb-column__inner-wrap\">\n<p align=\"center\"><iframe name=\"contactform\" src=\"about:blank\" marginheight=\"0\" marginwidth=\"0\" width=\"640\" height=\"980\" frameborder=\"0\">Na\u010d\u00edt\u00e1n\u00ed\u2026<\/iframe><\/p>\n<\/div><\/div>\n<\/div><\/section>","protected":false},"excerpt":{"rendered":"<p>If you would like to reach us with questions or concerns, you may use the form below. Please note, as per GPDR regulation, we wish to inform you the contact form uses 3rd party cookies (Google Forms) for the purposes of logging your response. If you consent to the use of 3rd party cookies, Click [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_uag_custom_page_level_css":"","site-sidebar-layout":"default","site-content-layout":"default","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"hf_cat_page":[],"uagb_featured_image_src":{"full":false,"thumbnail":false,"medium":false,"medium_large":false,"large":false,"1536x1536":false,"2048x2048":false,"trp-custom-language-flag":false},"uagb_author_info":{"display_name":"SOE","author_link":"https:\/\/supcom.standardof.net\/cs\/author\/k-tastic\/"},"uagb_comment_info":0,"uagb_excerpt":"If you would like to reach us with questions or concerns, you may use the form below. Please note, as per GPDR regulation, we wish to inform you the contact form uses 3rd party cookies (Google Forms) for the purposes of logging your response. If you consent to the use of 3rd party cookies, Click&hellip;","_links":{"self":[{"href":"https:\/\/supcom.standardof.net\/cs\/wp-json\/wp\/v2\/pages\/1149"}],"collection":[{"href":"https:\/\/supcom.standardof.net\/cs\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/supcom.standardof.net\/cs\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/supcom.standardof.net\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/supcom.standardof.net\/cs\/wp-json\/wp\/v2\/comments?post=1149"}],"version-history":[{"count":0,"href":"https:\/\/supcom.standardof.net\/cs\/wp-json\/wp\/v2\/pages\/1149\/revisions"}],"wp:attachment":[{"href":"https:\/\/supcom.standardof.net\/cs\/wp-json\/wp\/v2\/media?parent=1149"}],"wp:term":[{"taxonomy":"hf_cat_page","embeddable":true,"href":"https:\/\/supcom.standardof.net\/cs\/wp-json\/wp\/v2\/hf_cat_page?post=1149"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}