{"id":25901,"date":"2024-02-29T15:28:28","date_gmt":"2024-02-29T13:28:28","guid":{"rendered":"https:\/\/hostkoss.com\/b\/?p=25901"},"modified":"2024-07-10T11:21:16","modified_gmt":"2024-07-10T08:21:16","slug":"database","status":"publish","type":"post","link":"https:\/\/hostkoss.com\/b\/cs\/database\/","title":{"rendered":"Co je to datab\u00e1ze a pro\u010d je d\u016fle\u017eit\u00e1 pro podnik\u00e1n\u00ed"},"content":{"rendered":"\n

Datab\u00e1ze jsou souborem informac\u00ed, kter\u00e9 jsou obvykle uspo\u0159\u00e1d\u00e1ny do tabulek.<\/strong> Data v datab\u00e1z\u00edch jsou ulo\u017eena tak, aby je bylo mo\u017en\u00e9 snadno vyhledat a pou\u017e\u00edt pomoc\u00ed po\u010d\u00edta\u010dov\u00e9ho programu.<\/p>\n\n\n\n

Datab\u00e1ze jsou pro podniky d\u016fle\u017eit\u00e9, proto\u017ee se v nich ukl\u00e1daj\u00ed informace, kter\u00e9<\/strong> jsou pro chod podniku nezbytn\u00e9, nap\u0159\u00edklad informace o z\u00e1kazn\u00edc\u00edch, skladov\u00e9 z\u00e1znamy a objedn\u00e1vky. K tomuto typu informac\u00ed lze p\u0159istupovat rychle a p\u0159esn\u011b, ani\u017e by bylo nutn\u00e9 t\u0159\u00eddit stohy pap\u00edrov\u00fdch z\u00e1znam\u016f nebo si pamatovat, kde jsou jednotliv\u00e9 \u00fadaje ulo\u017eeny.<\/p>\n\n\n\n

Co jsou to datab\u00e1ze RDBMS, NoSQL a SQL?<\/h2>\n\n\n\n

Syst\u00e9m pro spr\u00e1vu rela\u010dn\u00edch datab\u00e1z\u00ed (RDBMS<\/strong> ) je typ datab\u00e1ze, kter\u00e1 slou\u017e\u00ed k ukl\u00e1d\u00e1n\u00ed, vyhled\u00e1v\u00e1n\u00ed a spr\u00e1v\u011b dat v tabulk\u00e1ch. Ukl\u00e1d\u00e1 data v \u0159\u00e1dc\u00edch a sloupc\u00edch.<\/p>\n\n\n\n

Datab\u00e1ze NoSQL jsou navr\u017eeny tak, aby \u0159e\u0161ily probl\u00e9my, kter\u00e9<\/strong> DBMS \u0159e\u0161it nemohou, nap\u0159\u00edklad ukl\u00e1d\u00e1n\u00ed nestrukturovan\u00fdch dat, distribuovan\u00e9 ukl\u00e1d\u00e1n\u00ed, \u0161k\u00e1lovatelnost a v\u00fdkon.<\/p>\n\n\n\n

Datab\u00e1ze SQL jsou rychlej\u0161\u00ed ne\u017e datab\u00e1ze NoSQL<\/strong>, ale ze sv\u00e9 podstaty nejsou \u0161k\u00e1lovateln\u00e9. Nepodporuj\u00ed dob\u0159e nestrukturovan\u00e1 data, a proto je nelze pou\u017e\u00edt pro anal\u00fdzu velk\u00fdch objem\u016f dat.<\/p>\n\n\n\n

Jak datab\u00e1ze funguje<\/h2>\n\n\n\n

Rela\u010dn\u00ed datab\u00e1ze ukl\u00e1d\u00e1 data do tabulek.<\/strong> Tabulky se skl\u00e1daj\u00ed z \u0159\u00e1dk\u016f a sloupc\u016f. \u0158\u00e1dek je jeden z\u00e1znam v tabulce a sloupec je konkr\u00e9tn\u00ed pole v ka\u017ed\u00e9m \u0159\u00e1dku.<\/p>\n\n\n\n

Sloupcov\u00e1 datab\u00e1ze ukl\u00e1d\u00e1 data ve sloupc\u00edch,<\/strong> co\u017e jsou ur\u010dit\u00e1 pole v ka\u017ed\u00e9m \u0159\u00e1dku. Sloupce jsou ulo\u017eeny v se\u0159azen\u00e9m po\u0159ad\u00ed, aby se nad nimi daly snadn\u011bji prov\u00e1d\u011bt dotazy.<\/p>\n\n\n\n

\u00dalo\u017ei\u0161t\u011b kl\u00ed\u010d\u016f a hodnot ukl\u00e1daj\u00ed data bu\u010f<\/strong> jako p\u00e1ry kl\u00ed\u010d-hodnota, nebo jako seznamy kl\u00ed\u010d\u016f a hodnot. To znamen\u00e1, \u017ee v\u0161echna data jsou ulo\u017eena jako objekty a k jejich uspo\u0159\u00e1d\u00e1n\u00ed nejsou pot\u0159eba \u017e\u00e1dn\u00e9 tabulky ani \u0159\u00e1dky.<\/p>\n\n\n\n

Typy datab\u00e1z\u00ed a v\u00fdhody\/nev\u00fdhody jednotliv\u00fdch typ\u016f<\/h2>\n\n\n\n

Rela\u010dn\u00ed datab\u00e1ze jsou<\/strong> dnes nej\u010dast\u011bji pou\u017e\u00edvan\u00fdm typem datab\u00e1ze<\/strong>. Ukl\u00e1daj\u00ed data do tabulek s \u0159\u00e1dky a sloupci. K t\u011bmto datab\u00e1z\u00edm lze p\u0159istupovat pomoc\u00ed jazyka SQL, kter\u00fd je k tomuto \u00fa\u010delu ur\u010den.<\/p>\n\n\n\n

Sloupcov\u00e9 datab\u00e1ze ukl\u00e1daj\u00ed data ve form\u011b sloupc\u016f, co\u017e<\/strong> je efektivn\u011bj\u0161\u00ed ne\u017e \u0159\u00e1dkov\u00e9 ukl\u00e1d\u00e1n\u00ed. To umo\u017e\u0148uje rychlej\u0161\u00ed dotazy a aktualizace datab\u00e1ze. Sloupcov\u00e9 datab\u00e1ze tak\u00e9 zab\u00edraj\u00ed m\u00e9n\u011b pam\u011bti ne\u017e datab\u00e1ze zalo\u017een\u00e9 na \u0159\u00e1dc\u00edch, co\u017e znamen\u00e1, \u017ee ke sv\u00e9mu provozu pot\u0159ebuj\u00ed m\u00e9n\u011b pam\u011bti RAM.<\/p>\n\n\n\n

Kl\u00ed\u010dov\u00e1 a hodnotov\u00e1 \u00falo\u017ei\u0161t\u011b se od rela\u010dn\u00edch a<\/strong> sloupcov\u00fdch datab\u00e1z\u00ed li\u0161\u00ed<\/strong> t\u00edm, \u017ee nevy\u017eaduj\u00ed p\u0159edb\u011b\u017en\u00fd n\u00e1vrh sch\u00e9matu a umo\u017e\u0148uj\u00ed ukl\u00e1dat data v libovoln\u00e9m po\u0159ad\u00ed bez nutnosti p\u0159edem definovat jejich strukturu.<\/p>\n\n\n\n

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Z\u00e1v\u011br:<\/strong>
Datab\u00e1ze je soubor dat uspo\u0159\u00e1dan\u00fd tak, aby je lid\u00e9 mohli sn\u00e1ze naj\u00edt a pou\u017e\u00edvat. Datab\u00e1ze jsou ned\u00edlnou sou\u010d\u00e1st\u00ed ka\u017ed\u00e9 organizace. Pom\u00e1haj\u00ed uspo\u0159\u00e1dat v\u0161echna data shrom\u00e1\u017ed\u011bn\u00e1 spole\u010dnost\u00ed a zp\u0159\u00edstupnit je. Mohou b\u00fdt pou\u017eity k r\u016fzn\u00fdm \u00fa\u010del\u016fm, nap\u0159\u00edklad k ukl\u00e1d\u00e1n\u00ed informac\u00ed o z\u00e1kazn\u00edc\u00edch, zpracov\u00e1n\u00ed transakc\u00ed nebo evidenci z\u00e1sob.<\/p>\n<\/blockquote>\n\n\n\n

P\u0159e\u010dt\u011bte si tak\u00e9:<\/strong><\/p>\n\n\n\n