WordPressでSQLを記述してデータベース操作

SELECT 抽出 ( 1レコード )

$sql = “SELECT count(*) as cnt FROM sample_table WHERE post_author = %d”;
$prepared = $wpdb->prepare($sql, esc_sql($user_id));
$post_cnt = $wpdb->get_row($prepared);

return $post_cnt->cnt;

%d,%f,%s(整数,浮動小数点数,文字列)

SELECT 抽出 ( 複数レコード )

$sql = “SELECT * FROM sample_table WHERE post_author = %d”;
$prepared = $wpdb->prepare($sql, esc_sql($user_id));
$posts = $wpdb->get_results($prepared);

if ( $posts ) {
　foreach ( $posts as $key => $row ) {
　　echo $row->ID;
　}
}

INSERT 追加

$wpdb->insert( ‘sample_table’,
　array( ‘post_author’ => $user_id,’ins_date’ => $data[‘ins_date’] )
);

UPDATE 更新

$wpdb->update( ‘sample_table’,
　array( ‘post_author’ => $user_id,’upd_date’ => $data[‘ins_date’] ),
　array( ‘id’ => 123 )
);

DELETE 削除

$wpdb->delete( ‘sample_table’,
　array( ‘id’ => 123 )
);