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  10.   <title>Database Metadata &mdash; CodeIgniter 3.1.11 documentation</title>
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    142. 

  142. <li class="toctree-l2"><a class="reference internal" href="../libraries/migration.html">Migrations Class</a></li>
    143. 

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  145. <li class="toctree-l2"><a class="reference internal" href="../libraries/parser.html">Template Parser Class</a></li>
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  147. <li class="toctree-l2"><a class="reference internal" href="../libraries/sessions.html">Session Library</a></li>
    148. 

  148. <li class="toctree-l2"><a class="reference internal" href="../libraries/table.html">HTML Table Class</a></li>
    149. 

  149. <li class="toctree-l2"><a class="reference internal" href="../libraries/trackback.html">Trackback Class</a></li>
    150. 

  150. <li class="toctree-l2"><a class="reference internal" href="../libraries/typography.html">Typography Class</a></li>
    151. 

  151. <li class="toctree-l2"><a class="reference internal" href="../libraries/unit_testing.html">Unit Testing Class</a></li>
    152. 

  152. <li class="toctree-l2"><a class="reference internal" href="../libraries/uri.html">URI Class</a></li>
    153. 

  153. <li class="toctree-l2"><a class="reference internal" href="../libraries/user_agent.html">User Agent Class</a></li>
    154. 

  154. <li class="toctree-l2"><a class="reference internal" href="../libraries/xmlrpc.html">XML-RPC and XML-RPC Server Classes</a></li>
    155. 

  155. <li class="toctree-l2"><a class="reference internal" href="../libraries/zip.html">Zip Encoding Class</a></li>
    156. 

  156. </ul>
    157. 

  157. </li>
    158. 

  158. </ul>
    159. 

  159. <ul class="current">
    160. 

  160. <li class="toctree-l1 current"><a class="reference internal" href="index.html">Database Reference</a><ul class="current">
    161. 

  161. <li class="toctree-l2"><a class="reference internal" href="examples.html">Quick Start: Usage Examples</a></li>
    162. 

  162. <li class="toctree-l2"><a class="reference internal" href="configuration.html">Database Configuration</a></li>
    163. 

  163. <li class="toctree-l2"><a class="reference internal" href="connecting.html">Connecting to a Database</a></li>
    164. 

  164. <li class="toctree-l2"><a class="reference internal" href="queries.html">Running Queries</a></li>
    165. 

  165. <li class="toctree-l2"><a class="reference internal" href="results.html">Generating Query Results</a></li>
    166. 

  166. <li class="toctree-l2"><a class="reference internal" href="helpers.html">Query Helper Functions</a></li>
    167. 

  167. <li class="toctree-l2"><a class="reference internal" href="query_builder.html">Query Builder Class</a></li>
    168. 

  168. <li class="toctree-l2"><a class="reference internal" href="transactions.html">Transactions</a></li>
    169. 

  169. <li class="toctree-l2 current"><a class="current reference internal" href="#">Getting MetaData</a></li>
    170. 

  170. <li class="toctree-l2"><a class="reference internal" href="call_function.html">Custom Function Calls</a></li>
    171. 

  171. <li class="toctree-l2"><a class="reference internal" href="caching.html">Query Caching</a></li>
    172. 

  172. <li class="toctree-l2"><a class="reference internal" href="forge.html">Database Manipulation with Database Forge</a></li>
    173. 

  173. <li class="toctree-l2"><a class="reference internal" href="utilities.html">Database Utilities Class</a></li>
    174. 

  174. <li class="toctree-l2"><a class="reference internal" href="db_driver_reference.html">Database Driver Reference</a></li>
    175. 

  175. </ul>
    176. 

  176. </li>
    177. 

  177. </ul>
    178. 

  178. <ul>
    179. 

  179. <li class="toctree-l1"><a class="reference internal" href="../helpers/index.html">Helpers</a><ul>
    180. 

  180. <li class="toctree-l2"><a class="reference internal" href="../helpers/array_helper.html">Array Helper</a></li>
    181. 

  181. <li class="toctree-l2"><a class="reference internal" href="../helpers/captcha_helper.html">CAPTCHA Helper</a></li>
    182. 

  182. <li class="toctree-l2"><a class="reference internal" href="../helpers/cookie_helper.html">Cookie Helper</a></li>
    183. 

  183. <li class="toctree-l2"><a class="reference internal" href="../helpers/date_helper.html">Date Helper</a></li>
    184. 

  184. <li class="toctree-l2"><a class="reference internal" href="../helpers/directory_helper.html">Directory Helper</a></li>
    185. 

  185. <li class="toctree-l2"><a class="reference internal" href="../helpers/download_helper.html">Download Helper</a></li>
    186. 

  186. <li class="toctree-l2"><a class="reference internal" href="../helpers/email_helper.html">Email Helper</a></li>
    187. 

  187. <li class="toctree-l2"><a class="reference internal" href="../helpers/file_helper.html">File Helper</a></li>
    188. 

  188. <li class="toctree-l2"><a class="reference internal" href="../helpers/form_helper.html">Form Helper</a></li>
    189. 

  189. <li class="toctree-l2"><a class="reference internal" href="../helpers/html_helper.html">HTML Helper</a></li>
    190. 

  190. <li class="toctree-l2"><a class="reference internal" href="../helpers/inflector_helper.html">Inflector Helper</a></li>
    191. 

  191. <li class="toctree-l2"><a class="reference internal" href="../helpers/language_helper.html">Language Helper</a></li>
    192. 

  192. <li class="toctree-l2"><a class="reference internal" href="../helpers/number_helper.html">Number Helper</a></li>
    193. 

  193. <li class="toctree-l2"><a class="reference internal" href="../helpers/path_helper.html">Path Helper</a></li>
    194. 

  194. <li class="toctree-l2"><a class="reference internal" href="../helpers/security_helper.html">Security Helper</a></li>
    195. 

  195. <li class="toctree-l2"><a class="reference internal" href="../helpers/smiley_helper.html">Smiley Helper</a></li>
    196. 

  196. <li class="toctree-l2"><a class="reference internal" href="../helpers/string_helper.html">String Helper</a></li>
    197. 

  197. <li class="toctree-l2"><a class="reference internal" href="../helpers/text_helper.html">Text Helper</a></li>
    198. 

  198. <li class="toctree-l2"><a class="reference internal" href="../helpers/typography_helper.html">Typography Helper</a></li>
    199. 

  199. <li class="toctree-l2"><a class="reference internal" href="../helpers/url_helper.html">URL Helper</a></li>
    200. 

  200. <li class="toctree-l2"><a class="reference internal" href="../helpers/xml_helper.html">XML Helper</a></li>
    201. 

  201. </ul>
    202. 

  202. </li>
    203. 

  203. </ul>
    204. 

  204. 

  205.       </div>
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  206.     
    207. 

  207.       
    208. 

  208.   </div>
    209. 

  209. </div>
    210. 

  210. <div id="nav2">
    211. 

  211.   <a href="#" id="openToc">
    212. 

  212.     <img src="data:image/jpeg;base64,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" title="Toggle Table of Contents" alt="Toggle Table of Contents" />
    213. 

  213.   </a>
    214. 

  214. </div>
    215. 

  215. 

  216.   <div class="wy-grid-for-nav">
    217. 

  217. 

  218.     
    219. 

  219.     <nav data-toggle="wy-nav-shift" class="wy-nav-side">
    220. 

  220.       <div class="wy-side-nav-search">
    221. 

  221.         
    222. 

  222.           <a href="../index.html" class="fa fa-home"> CodeIgniter</a>
    223. 

  223.         
    224. 

  224.         
    225. 

  225. <div role="search">
    226. 

  226.   <form id="rtd-search-form" class="wy-form" action="../search.html" method="get">
    227. 

  227.     <input type="text" name="q" placeholder="Search docs" />
    228. 

  228.     <input type="hidden" name="check_keywords" value="yes" />
    229. 

  229.     <input type="hidden" name="area" value="default" />
    230. 

  230.   </form>
    231. 

  231. </div>
    232. 

  232.       </div>
    233. 

  233. 

  234.       <div class="wy-menu wy-menu-vertical" data-spy="affix" role="navigation" aria-label="main navigation">
    235. 

  235.         
    236. 

  236.           
    237. 

  237.           
    238. 

  238.               <ul>
    239. 

  239. <li class="toctree-l1"><a class="reference internal" href="../general/welcome.html">Welcome to CodeIgniter</a></li>
    240. 

  240. </ul>
    241. 

  241. <ul>
    242. 

  242. <li class="toctree-l1"><a class="reference internal" href="../installation/index.html">Installation Instructions</a><ul>
    243. 

  243. <li class="toctree-l2"><a class="reference internal" href="../installation/downloads.html">Downloading CodeIgniter</a></li>
    244. 

  244. <li class="toctree-l2"><a class="reference internal" href="../installation/index.html">Installation Instructions</a></li>
    245. 

  245. <li class="toctree-l2"><a class="reference internal" href="../installation/upgrading.html">Upgrading From a Previous Version</a></li>
    246. 

  246. <li class="toctree-l2"><a class="reference internal" href="../installation/troubleshooting.html">Troubleshooting</a></li>
    247. 

  247. </ul>
    248. 

  248. </li>
    249. 

  249. </ul>
    250. 

  250. <ul>
    251. 

  251. <li class="toctree-l1"><a class="reference internal" href="../overview/index.html">CodeIgniter Overview</a><ul>
    252. 

  252. <li class="toctree-l2"><a class="reference internal" href="../overview/getting_started.html">Getting Started</a></li>
    253. 

  253. <li class="toctree-l2"><a class="reference internal" href="../overview/at_a_glance.html">CodeIgniter at a Glance</a></li>
    254. 

  254. <li class="toctree-l2"><a class="reference internal" href="../overview/features.html">Supported Features</a></li>
    255. 

  255. <li class="toctree-l2"><a class="reference internal" href="../overview/appflow.html">Application Flow Chart</a></li>
    256. 

  256. <li class="toctree-l2"><a class="reference internal" href="../overview/mvc.html">Model-View-Controller</a></li>
    257. 

  257. <li class="toctree-l2"><a class="reference internal" href="../overview/goals.html">Architectural Goals</a></li>
    258. 

  258. </ul>
    259. 

  259. </li>
    260. 

  260. </ul>
    261. 

  261. <ul>
    262. 

  262. <li class="toctree-l1"><a class="reference internal" href="../tutorial/index.html">Tutorial</a><ul>
    263. 

  263. <li class="toctree-l2"><a class="reference internal" href="../tutorial/static_pages.html">Static pages</a></li>
    264. 

  264. <li class="toctree-l2"><a class="reference internal" href="../tutorial/news_section.html">News section</a></li>
    265. 

  265. <li class="toctree-l2"><a class="reference internal" href="../tutorial/create_news_items.html">Create news items</a></li>
    266. 

  266. <li class="toctree-l2"><a class="reference internal" href="../tutorial/conclusion.html">Conclusion</a></li>
    267. 

  267. </ul>
    268. 

  268. </li>
    269. 

  269. </ul>
    270. 

  270. <ul>
    271. 

  271. <li class="toctree-l1"><a class="reference internal" href="../contributing/index.html">Contributing to CodeIgniter</a><ul>
    272. 

  272. <li class="toctree-l2"><a class="reference internal" href="../documentation/index.html">Writing CodeIgniter Documentation</a></li>
    273. 

  273. <li class="toctree-l2"><a class="reference internal" href="../DCO.html">Developer’s Certificate of Origin 1.1</a></li>
    274. 

  274. </ul>
    275. 

  275. </li>
    276. 

  276. </ul>
    277. 

  277. <ul>
    278. 

  278. <li class="toctree-l1"><a class="reference internal" href="../general/index.html">General Topics</a><ul>
    279. 

  279. <li class="toctree-l2"><a class="reference internal" href="../general/urls.html">CodeIgniter URLs</a></li>
    280. 

  280. <li class="toctree-l2"><a class="reference internal" href="../general/controllers.html">Controllers</a></li>
    281. 

  281. <li class="toctree-l2"><a class="reference internal" href="../general/reserved_names.html">Reserved Names</a></li>
    282. 

  282. <li class="toctree-l2"><a class="reference internal" href="../general/views.html">Views</a></li>
    283. 

  283. <li class="toctree-l2"><a class="reference internal" href="../general/models.html">Models</a></li>
    284. 

  284. <li class="toctree-l2"><a class="reference internal" href="../general/helpers.html">Helpers</a></li>
    285. 

  285. <li class="toctree-l2"><a class="reference internal" href="../general/libraries.html">Using CodeIgniter Libraries</a></li>
    286. 

  286. <li class="toctree-l2"><a class="reference internal" href="../general/creating_libraries.html">Creating Libraries</a></li>
    287. 

  287. <li class="toctree-l2"><a class="reference internal" href="../general/drivers.html">Using CodeIgniter Drivers</a></li>
    288. 

  288. <li class="toctree-l2"><a class="reference internal" href="../general/creating_drivers.html">Creating Drivers</a></li>
    289. 

  289. <li class="toctree-l2"><a class="reference internal" href="../general/core_classes.html">Creating Core System Classes</a></li>
    290. 

  290. <li class="toctree-l2"><a class="reference internal" href="../general/ancillary_classes.html">Creating Ancillary Classes</a></li>
    291. 

  291. <li class="toctree-l2"><a class="reference internal" href="../general/hooks.html">Hooks - Extending the Framework Core</a></li>
    292. 

  292. <li class="toctree-l2"><a class="reference internal" href="../general/autoloader.html">Auto-loading Resources</a></li>
    293. 

  293. <li class="toctree-l2"><a class="reference internal" href="../general/common_functions.html">Common Functions</a></li>
    294. 

  294. <li class="toctree-l2"><a class="reference internal" href="../general/compatibility_functions.html">Compatibility Functions</a></li>
    295. 

  295. <li class="toctree-l2"><a class="reference internal" href="../general/routing.html">URI Routing</a></li>
    296. 

  296. <li class="toctree-l2"><a class="reference internal" href="../general/errors.html">Error Handling</a></li>
    297. 

  297. <li class="toctree-l2"><a class="reference internal" href="../general/caching.html">Caching</a></li>
    298. 

  298. <li class="toctree-l2"><a class="reference internal" href="../general/profiling.html">Profiling Your Application</a></li>
    299. 

  299. <li class="toctree-l2"><a class="reference internal" href="../general/cli.html">Running via the CLI</a></li>
    300. 

  300. <li class="toctree-l2"><a class="reference internal" href="../general/managing_apps.html">Managing your Applications</a></li>
    301. 

  301. <li class="toctree-l2"><a class="reference internal" href="../general/environments.html">Handling Multiple Environments</a></li>
    302. 

  302. <li class="toctree-l2"><a class="reference internal" href="../general/alternative_php.html">Alternate PHP Syntax for View Files</a></li>
    303. 

  303. <li class="toctree-l2"><a class="reference internal" href="../general/security.html">Security</a></li>
    304. 

  304. <li class="toctree-l2"><a class="reference internal" href="../general/styleguide.html">PHP Style Guide</a></li>
    305. 

  305. </ul>
    306. 

  306. </li>
    307. 

  307. </ul>
    308. 

  308. <ul>
    309. 

  309. <li class="toctree-l1"><a class="reference internal" href="../libraries/index.html">Libraries</a><ul>
    310. 

  310. <li class="toctree-l2"><a class="reference internal" href="../libraries/benchmark.html">Benchmarking Class</a></li>
    311. 

  311. <li class="toctree-l2"><a class="reference internal" href="../libraries/caching.html">Caching Driver</a></li>
    312. 

  312. <li class="toctree-l2"><a class="reference internal" href="../libraries/calendar.html">Calendaring Class</a></li>
    313. 

  313. <li class="toctree-l2"><a class="reference internal" href="../libraries/cart.html">Shopping Cart Class</a></li>
    314. 

  314. <li class="toctree-l2"><a class="reference internal" href="../libraries/config.html">Config Class</a></li>
    315. 

  315. <li class="toctree-l2"><a class="reference internal" href="../libraries/email.html">Email Class</a></li>
    316. 

  316. <li class="toctree-l2"><a class="reference internal" href="../libraries/encrypt.html">Encrypt Class</a></li>
    317. 

  317. <li class="toctree-l2"><a class="reference internal" href="../libraries/encryption.html">Encryption Library</a></li>
    318. 

  318. <li class="toctree-l2"><a class="reference internal" href="../libraries/file_uploading.html">File Uploading Class</a></li>
    319. 

  319. <li class="toctree-l2"><a class="reference internal" href="../libraries/form_validation.html">Form Validation</a></li>
    320. 

  320. <li class="toctree-l2"><a class="reference internal" href="../libraries/ftp.html">FTP Class</a></li>
    321. 

  321. <li class="toctree-l2"><a class="reference internal" href="../libraries/image_lib.html">Image Manipulation Class</a></li>
    322. 

  322. <li class="toctree-l2"><a class="reference internal" href="../libraries/input.html">Input Class</a></li>
    323. 

  323. <li class="toctree-l2"><a class="reference internal" href="../libraries/javascript.html">Javascript Class</a></li>
    324. 

  324. <li class="toctree-l2"><a class="reference internal" href="../libraries/language.html">Language Class</a></li>
    325. 

  325. <li class="toctree-l2"><a class="reference internal" href="../libraries/loader.html">Loader Class</a></li>
    326. 

  326. <li class="toctree-l2"><a class="reference internal" href="../libraries/migration.html">Migrations Class</a></li>
    327. 

  327. <li class="toctree-l2"><a class="reference internal" href="../libraries/output.html">Output Class</a></li>
    328. 

  328. <li class="toctree-l2"><a class="reference internal" href="../libraries/pagination.html">Pagination Class</a></li>
    329. 

  329. <li class="toctree-l2"><a class="reference internal" href="../libraries/parser.html">Template Parser Class</a></li>
    330. 

  330. <li class="toctree-l2"><a class="reference internal" href="../libraries/security.html">Security Class</a></li>
    331. 

  331. <li class="toctree-l2"><a class="reference internal" href="../libraries/sessions.html">Session Library</a></li>
    332. 

  332. <li class="toctree-l2"><a class="reference internal" href="../libraries/table.html">HTML Table Class</a></li>
    333. 

  333. <li class="toctree-l2"><a class="reference internal" href="../libraries/trackback.html">Trackback Class</a></li>
    334. 

  334. <li class="toctree-l2"><a class="reference internal" href="../libraries/typography.html">Typography Class</a></li>
    335. 

  335. <li class="toctree-l2"><a class="reference internal" href="../libraries/unit_testing.html">Unit Testing Class</a></li>
    336. 

  336. <li class="toctree-l2"><a class="reference internal" href="../libraries/uri.html">URI Class</a></li>
    337. 

  337. <li class="toctree-l2"><a class="reference internal" href="../libraries/user_agent.html">User Agent Class</a></li>
    338. 

  338. <li class="toctree-l2"><a class="reference internal" href="../libraries/xmlrpc.html">XML-RPC and XML-RPC Server Classes</a></li>
    339. 

  339. <li class="toctree-l2"><a class="reference internal" href="../libraries/zip.html">Zip Encoding Class</a></li>
    340. 

  340. </ul>
    341. 

  341. </li>
    342. 

  342. </ul>
    343. 

  343. <ul class="current">
    344. 

  344. <li class="toctree-l1 current"><a class="reference internal" href="index.html">Database Reference</a><ul class="current">
    345. 

  345. <li class="toctree-l2"><a class="reference internal" href="examples.html">Quick Start: Usage Examples</a></li>
    346. 

  346. <li class="toctree-l2"><a class="reference internal" href="configuration.html">Database Configuration</a></li>
    347. 

  347. <li class="toctree-l2"><a class="reference internal" href="connecting.html">Connecting to a Database</a></li>
    348. 

  348. <li class="toctree-l2"><a class="reference internal" href="queries.html">Running Queries</a></li>
    349. 

  349. <li class="toctree-l2"><a class="reference internal" href="results.html">Generating Query Results</a></li>
    350. 

  350. <li class="toctree-l2"><a class="reference internal" href="helpers.html">Query Helper Functions</a></li>
    351. 

  351. <li class="toctree-l2"><a class="reference internal" href="query_builder.html">Query Builder Class</a></li>
    352. 

  352. <li class="toctree-l2"><a class="reference internal" href="transactions.html">Transactions</a></li>
    353. 

  353. <li class="toctree-l2 current"><a class="current reference internal" href="#">Getting MetaData</a></li>
    354. 

  354. <li class="toctree-l2"><a class="reference internal" href="call_function.html">Custom Function Calls</a></li>
    355. 

  355. <li class="toctree-l2"><a class="reference internal" href="caching.html">Query Caching</a></li>
    356. 

  356. <li class="toctree-l2"><a class="reference internal" href="forge.html">Database Manipulation with Database Forge</a></li>
    357. 

  357. <li class="toctree-l2"><a class="reference internal" href="utilities.html">Database Utilities Class</a></li>
    358. 

  358. <li class="toctree-l2"><a class="reference internal" href="db_driver_reference.html">Database Driver Reference</a></li>
    359. 

  359. </ul>
    360. 

  360. </li>
    361. 

  361. </ul>
    362. 

  362. <ul>
    363. 

  363. <li class="toctree-l1"><a class="reference internal" href="../helpers/index.html">Helpers</a><ul>
    364. 

  364. <li class="toctree-l2"><a class="reference internal" href="../helpers/array_helper.html">Array Helper</a></li>
    365. 

  365. <li class="toctree-l2"><a class="reference internal" href="../helpers/captcha_helper.html">CAPTCHA Helper</a></li>
    366. 

  366. <li class="toctree-l2"><a class="reference internal" href="../helpers/cookie_helper.html">Cookie Helper</a></li>
    367. 

  367. <li class="toctree-l2"><a class="reference internal" href="../helpers/date_helper.html">Date Helper</a></li>
    368. 

  368. <li class="toctree-l2"><a class="reference internal" href="../helpers/directory_helper.html">Directory Helper</a></li>
    369. 

  369. <li class="toctree-l2"><a class="reference internal" href="../helpers/download_helper.html">Download Helper</a></li>
    370. 

  370. <li class="toctree-l2"><a class="reference internal" href="../helpers/email_helper.html">Email Helper</a></li>
    371. 

  371. <li class="toctree-l2"><a class="reference internal" href="../helpers/file_helper.html">File Helper</a></li>
    372. 

  372. <li class="toctree-l2"><a class="reference internal" href="../helpers/form_helper.html">Form Helper</a></li>
    373. 

  373. <li class="toctree-l2"><a class="reference internal" href="../helpers/html_helper.html">HTML Helper</a></li>
    374. 

  374. <li class="toctree-l2"><a class="reference internal" href="../helpers/inflector_helper.html">Inflector Helper</a></li>
    375. 

  375. <li class="toctree-l2"><a class="reference internal" href="../helpers/language_helper.html">Language Helper</a></li>
    376. 

  376. <li class="toctree-l2"><a class="reference internal" href="../helpers/number_helper.html">Number Helper</a></li>
    377. 

  377. <li class="toctree-l2"><a class="reference internal" href="../helpers/path_helper.html">Path Helper</a></li>
    378. 

  378. <li class="toctree-l2"><a class="reference internal" href="../helpers/security_helper.html">Security Helper</a></li>
    379. 

  379. <li class="toctree-l2"><a class="reference internal" href="../helpers/smiley_helper.html">Smiley Helper</a></li>
    380. 

  380. <li class="toctree-l2"><a class="reference internal" href="../helpers/string_helper.html">String Helper</a></li>
    381. 

  381. <li class="toctree-l2"><a class="reference internal" href="../helpers/text_helper.html">Text Helper</a></li>
    382. 

  382. <li class="toctree-l2"><a class="reference internal" href="../helpers/typography_helper.html">Typography Helper</a></li>
    383. 

  383. <li class="toctree-l2"><a class="reference internal" href="../helpers/url_helper.html">URL Helper</a></li>
    384. 

  384. <li class="toctree-l2"><a class="reference internal" href="../helpers/xml_helper.html">XML Helper</a></li>
    385. 

  385. </ul>
    386. 

  386. </li>
    387. 

  387. </ul>
    388. 

  388. 

  389.           
    390. 

  390.         
    391. 

  391.       </div>
    392. 

  392.       &nbsp;
    393. 

  393.     </nav>
    394. 

  394. 

  395.     <section data-toggle="wy-nav-shift" class="wy-nav-content-wrap">
    396. 

  396. 

  397.       
    398. 

  398.       <nav class="wy-nav-top" role="navigation" aria-label="top navigation">
    399. 

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    425. 

  425.   <div class="section" id="database-metadata">
    426. 

  426. <h1>Database Metadata<a class="headerlink" href="#database-metadata" title="Permalink to this headline">¶</a></h1>
    427. 

  427. <div class="section" id="table-metadata">
    428. 

  428. <h2>Table MetaData<a class="headerlink" href="#table-metadata" title="Permalink to this headline">¶</a></h2>
    429. 

  429. <p>These functions let you fetch table information.</p>
    430. 

  430. <div class="section" id="list-the-tables-in-your-database">
    431. 

  431. <h3>List the Tables in Your Database<a class="headerlink" href="#list-the-tables-in-your-database" title="Permalink to this headline">¶</a></h3>
    432. 

  432. <p><strong>$this-&gt;db-&gt;list_tables();</strong></p>
    433. 

  433. <p>Returns an array containing the names of all the tables in the database
    434. 

  434. you are currently connected to. Example:</p>
    435. 

  435. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$tables</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">db</span><span class="o">-&gt;</span><span class="na">list_tables</span><span class="p">();</span>
    436. 

  436. 

  437. <span class="k">foreach</span> <span class="p">(</span><span class="nv">$tables</span> <span class="k">as</span> <span class="nv">$table</span><span class="p">)</span>
    438. 

  438. <span class="p">{</span>
    439. 

  439.         <span class="k">echo</span> <span class="nv">$table</span><span class="p">;</span>
    440. 

  440. <span class="p">}</span>
    441. 

  441. </pre></div>
    442. 

  442. </div>
    443. 

  443. </div>
    444. 

  444. <div class="section" id="determine-if-a-table-exists">
    445. 

  445. <h3>Determine If a Table Exists<a class="headerlink" href="#determine-if-a-table-exists" title="Permalink to this headline">¶</a></h3>
    446. 

  446. <p><strong>$this-&gt;db-&gt;table_exists();</strong></p>
    447. 

  447. <p>Sometimes it’s helpful to know whether a particular table exists before
    448. 

  448. running an operation on it. Returns a boolean TRUE/FALSE. Usage example:</p>
    449. 

  449. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="k">if</span> <span class="p">(</span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">db</span><span class="o">-&gt;</span><span class="na">table_exists</span><span class="p">(</span><span class="s1">&#39;table_name&#39;</span><span class="p">))</span>
    450. 

  450. <span class="p">{</span>
    451. 

  451.         <span class="c1">// some code...</span>
    452. 

  452. <span class="p">}</span>
    453. 

  453. </pre></div>
    454. 

  454. </div>
    455. 

  455. <div class="admonition note">
    456. 

  456. <p class="first admonition-title">Note</p>
    457. 

  457. <p class="last">Replace <em>table_name</em> with the name of the table you are looking for.</p>
    458. 

  458. </div>
    459. 

  459. </div>
    460. 

  460. </div>
    461. 

  461. <div class="section" id="field-metadata">
    462. 

  462. <h2>Field MetaData<a class="headerlink" href="#field-metadata" title="Permalink to this headline">¶</a></h2>
    463. 

  463. <div class="section" id="list-the-fields-in-a-table">
    464. 

  464. <h3>List the Fields in a Table<a class="headerlink" href="#list-the-fields-in-a-table" title="Permalink to this headline">¶</a></h3>
    465. 

  465. <p><strong>$this-&gt;db-&gt;list_fields()</strong></p>
    466. 

  466. <p>Returns an array containing the field names. This query can be called
    467. 

  467. two ways:</p>
    468. 

  468. <p>1. You can supply the table name and call it from the $this-&gt;db-&gt;
    469. 

  469. object:</p>
    470. 

  470. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$fields</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">db</span><span class="o">-&gt;</span><span class="na">list_fields</span><span class="p">(</span><span class="s1">&#39;table_name&#39;</span><span class="p">);</span>
    471. 

  471. 

  472. <span class="k">foreach</span> <span class="p">(</span><span class="nv">$fields</span> <span class="k">as</span> <span class="nv">$field</span><span class="p">)</span>
    473. 

  473. <span class="p">{</span>
    474. 

  474.         <span class="k">echo</span> <span class="nv">$field</span><span class="p">;</span>
    475. 

  475. <span class="p">}</span>
    476. 

  476. </pre></div>
    477. 

  477. </div>
    478. 

  478. <p>2. You can gather the field names associated with any query you run by
    479. 

  479. calling the function from your query result object:</p>
    480. 

  480. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$query</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">db</span><span class="o">-&gt;</span><span class="na">query</span><span class="p">(</span><span class="s1">&#39;SELECT * FROM some_table&#39;</span><span class="p">);</span>
    481. 

  481. 

  482. <span class="k">foreach</span> <span class="p">(</span><span class="nv">$query</span><span class="o">-&gt;</span><span class="na">list_fields</span><span class="p">()</span> <span class="k">as</span> <span class="nv">$field</span><span class="p">)</span>
    483. 

  483. <span class="p">{</span>
    484. 

  484.         <span class="k">echo</span> <span class="nv">$field</span><span class="p">;</span>
    485. 

  485. <span class="p">}</span>
    486. 

  486. </pre></div>
    487. 

  487. </div>
    488. 

  488. </div>
    489. 

  489. <div class="section" id="determine-if-a-field-is-present-in-a-table">
    490. 

  490. <h3>Determine If a Field is Present in a Table<a class="headerlink" href="#determine-if-a-field-is-present-in-a-table" title="Permalink to this headline">¶</a></h3>
    491. 

  491. <p><strong>$this-&gt;db-&gt;field_exists()</strong></p>
    492. 

  492. <p>Sometimes it’s helpful to know whether a particular field exists before
    493. 

  493. performing an action. Returns a boolean TRUE/FALSE. Usage example:</p>
    494. 

  494. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="k">if</span> <span class="p">(</span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">db</span><span class="o">-&gt;</span><span class="na">field_exists</span><span class="p">(</span><span class="s1">&#39;field_name&#39;</span><span class="p">,</span> <span class="s1">&#39;table_name&#39;</span><span class="p">))</span>
    495. 

  495. <span class="p">{</span>
    496. 

  496.         <span class="c1">// some code...</span>
    497. 

  497. <span class="p">}</span>
    498. 

  498. </pre></div>
    499. 

  499. </div>
    500. 

  500. <div class="admonition note">
    501. 

  501. <p class="first admonition-title">Note</p>
    502. 

  502. <p class="last">Replace <em>field_name</em> with the name of the column you are looking
    503. 

  503. for, and replace <em>table_name</em> with the name of the table you are
    504. 

  504. looking for.</p>
    505. 

  505. </div>
    506. 

  506. </div>
    507. 

  507. <div class="section" id="retrieve-field-metadata">
    508. 

  508. <h3>Retrieve Field Metadata<a class="headerlink" href="#retrieve-field-metadata" title="Permalink to this headline">¶</a></h3>
    509. 

  509. <p><strong>$this-&gt;db-&gt;field_data()</strong></p>
    510. 

  510. <p>Returns an array of objects containing field information.</p>
    511. 

  511. <p>Sometimes it’s helpful to gather the field names or other metadata, like
    512. 

  512. the column type, max length, etc.</p>
    513. 

  513. <div class="admonition note">
    514. 

  514. <p class="first admonition-title">Note</p>
    515. 

  515. <p class="last">Not all databases provide meta-data.</p>
    516. 

  516. </div>
    517. 

  517. <p>Usage example:</p>
    518. 

  518. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$fields</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">db</span><span class="o">-&gt;</span><span class="na">field_data</span><span class="p">(</span><span class="s1">&#39;table_name&#39;</span><span class="p">);</span>
    519. 

  519. 

  520. <span class="k">foreach</span> <span class="p">(</span><span class="nv">$fields</span> <span class="k">as</span> <span class="nv">$field</span><span class="p">)</span>
    521. 

  521. <span class="p">{</span>
    522. 

  522.         <span class="k">echo</span> <span class="nv">$field</span><span class="o">-&gt;</span><span class="na">name</span><span class="p">;</span>
    523. 

  523.         <span class="k">echo</span> <span class="nv">$field</span><span class="o">-&gt;</span><span class="na">type</span><span class="p">;</span>
    524. 

  524.         <span class="k">echo</span> <span class="nv">$field</span><span class="o">-&gt;</span><span class="na">max_length</span><span class="p">;</span>
    525. 

  525.         <span class="k">echo</span> <span class="nv">$field</span><span class="o">-&gt;</span><span class="na">primary_key</span><span class="p">;</span>
    526. 

  526. <span class="p">}</span>
    527. 

  527. </pre></div>
    528. 

  528. </div>
    529. 

  529. <p>If you have run a query already you can use the result object instead of
    530. 

  530. supplying the table name:</p>
    531. 

  531. <div class="highlight-ci"><div class="highlight"><pre><span></span><span class="nv">$query</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">db</span><span class="o">-&gt;</span><span class="na">query</span><span class="p">(</span><span class="s2">&quot;YOUR QUERY&quot;</span><span class="p">);</span>
    532. 

  532. <span class="nv">$fields</span> <span class="o">=</span> <span class="nv">$query</span><span class="o">-&gt;</span><span class="na">field_data</span><span class="p">();</span>
    533. 

  533. </pre></div>
    534. 

  534. </div>
    535. 

  535. <p>The following data is available from this function if supported by your
    536. 

  536. database:</p>
    537. 

  537. <ul class="simple">
    538. 

  538. <li>name - column name</li>
    539. 

  539. <li>max_length - maximum length of the column</li>
    540. 

  540. <li>primary_key - 1 if the column is a primary key</li>
    541. 

  541. <li>type - the type of the column</li>
    542. 

  542. </ul>
    543. 

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