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Update Russian version of FAQ.
This commit is contained in:
@ -1,7 +1,7 @@
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Otvety na chasto zadavaemye voprosy po PostgreSQL
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Otvety na chasto zadavaemye voprosy po PostgreSQL
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Data poslednego obnovleniya: Ponedel'nik 22 Aprelya 14:02:41 EDT 2003
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Data poslednego obnovleniya: Pyatnica 30 Maya 22:24:56 EDT 2003
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Anglijskij variant soprovozhdaet: Bryus Mom'yan (Bruce Momjian)
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Anglijskij variant soprovozhdaet: Bryus Mom'yan (Bruce Momjian)
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(pgman@candle.pha.pa.us)
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(pgman@candle.pha.pa.us)
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@ -66,9 +66,9 @@
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4.1) V chem otlichie mezhdu binarnym i normal'nym kursorom?
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4.1) V chem otlichie mezhdu binarnym i normal'nym kursorom?
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4.2) Kak vypolnit' SELECT tol'ko dlya neskol'kih pervyh strochek
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4.2) Kak vypolnit' SELECT tol'ko dlya neskol'kih pervyh strochek
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zaprosa?
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zaprosa? Dlya proizvol'noj stroki?
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4.3) Kak poluchit' spisok tablic ili drugih komponentov v psql?
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4.3) Kak poluchit' spisok tablic ili drugih komponentov v psql?
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4.4) Kak udalit' kolonku iz tablicy?
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4.4) Kak udalit' kolonku iz tablicy ili izmenit' eio tip dannyh?
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4.5) Kakovy maksimal'nye razmery dlya zapisej, tablic i bazy dannyh?
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4.5) Kakovy maksimal'nye razmery dlya zapisej, tablic i bazy dannyh?
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4.6) Kak mnogo diskovogo prostranstva v baze dannyh nuzhno dlya
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4.6) Kak mnogo diskovogo prostranstva v baze dannyh nuzhno dlya
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sohraneniya dannyh iz obychnogo tekstovogo fajla?
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sohraneniya dannyh iz obychnogo tekstovogo fajla?
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@ -709,6 +709,7 @@
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Smotrite opisanie na stranicah rukovodstva posvyaschennym DECLARE.
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Smotrite opisanie na stranicah rukovodstva posvyaschennym DECLARE.
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4.2) Kak vypolnit' SELECT tol'ko dlya neskol'kih pervyh strochek zaprosa?
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4.2) Kak vypolnit' SELECT tol'ko dlya neskol'kih pervyh strochek zaprosa?
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Proizvol'noj stroki?
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Smotrite stanicu rukovodstva posvyaschennuyu FETCH ili ispol'zujte
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Smotrite stanicu rukovodstva posvyaschennuyu FETCH ili ispol'zujte
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SELECT ... LIMIT....
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SELECT ... LIMIT....
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@ -719,6 +720,12 @@
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mozhet vydat' tol'ko neskol'ko pervyh zaproshennyh zapisej ili mozhet
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mozhet vydat' tol'ko neskol'ko pervyh zaproshennyh zapisej ili mozhet
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vypolnyat' zapros poka ne budut vydany zhelaemye zapisi.
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vypolnyat' zapros poka ne budut vydany zhelaemye zapisi.
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To SELECT a random row, use:
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SELECT col
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FROM tab
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ORDER BY random()
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LIMIT 1;
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4.3) Kak poluchit' spisok tablic ili drugih komponentov v psql?
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4.3) Kak poluchit' spisok tablic ili drugih komponentov v psql?
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Vy mozhete posmotret' ishodnyj kod psql v fajle
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Vy mozhete posmotret' ishodnyj kod psql v fajle
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@ -728,10 +735,10 @@
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chtoby `eta programma vydavala zaprosy, kotorye ona ispol'zuet dlya
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chtoby `eta programma vydavala zaprosy, kotorye ona ispol'zuet dlya
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vypolneniya zadannyh vami komand.
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vypolneniya zadannyh vami komand.
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4.4) Kak udalit' kolonku iz tablicy?
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4.4) Kak udalit' kolonku iz tablicy ili izmenit' ioio tip dannyh?
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`Eta funkcional'nost' byla dobavlena v vypusk 7.3 s operatorom ALTER
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DROP COLUMN funkcional'nost' byla dobavlena v vypusk 7.3 s operatorom
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TABLE DROP COLUMN. V rannih versiyah, mozhno sdelat' tak:
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ALTER TABLE DROP COLUMN. V rannih versiyah, mozhno sdelat' tak:
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BEGIN;
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BEGIN;
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LOCK TABLE old_table;
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LOCK TABLE old_table;
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SELECT ... -- vyborka vseh kolonok za isklyucheniem toj, kotoruyu hotite u
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SELECT ... -- vyborka vseh kolonok za isklyucheniem toj, kotoruyu hotite u
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@ -742,6 +749,13 @@ dalit'
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ALTER TABLE new_table RENAME TO old_table;
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ALTER TABLE new_table RENAME TO old_table;
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COMMIT;
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COMMIT;
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Dlya izmeneniya tipa dannyh kolonki, sdelajte tak:
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BEGIN;
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ALTER TABLE tab ADD COLUMN new_col new_data_type;
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UPDATE tab SET new_col = CAST(old_col AS new_data_type);
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ALTER TABLE DROP COLUMN old_col;
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COMMIT;
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4.5) Kakovy maksimal'nye razmery dlya zapisej, tablic i bazy dannyh?
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4.5) Kakovy maksimal'nye razmery dlya zapisej, tablic i bazy dannyh?
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Suschestvuyut sleduyuschie ogranicheniya:
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Suschestvuyut sleduyuschie ogranicheniya:
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@ -13,7 +13,7 @@
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alink="#0000ff">
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alink="#0000ff">
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<H1><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><> <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><> PostgreSQL</H1>
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<H1><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><> <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><> PostgreSQL</H1>
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<P><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>: <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 22 <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 14:02:41 EDT 2003</P>
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<P><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>: <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 30 <EFBFBD><EFBFBD><EFBFBD> 22:24:56 EDT 2003</P>
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<P><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>: <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> (Bruce Momjian) (<A href=
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<P><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>: <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> (Bruce Momjian) (<A href=
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"mailto:pgman@candle.pha.pa.us">pgman@candle.pha.pa.us</A>)<BR>
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"mailto:pgman@candle.pha.pa.us">pgman@candle.pha.pa.us</A>)<BR>
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@ -85,10 +85,11 @@
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<A href="#4.1">4.1</A>) <20> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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<A href="#4.1">4.1</A>) <20> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?<BR>
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?<BR>
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<A href="#4.2">4.2</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <SMALL>SELECT</SMALL> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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<A href="#4.2">4.2</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <SMALL>SELECT</SMALL> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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<20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?<BR>
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<20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>? <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?<BR>
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<A href="#4.3">4.3</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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<A href="#4.3">4.3</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <I>psql</I>?<BR>
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <I>psql</I>?<BR>
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<A href="#4.4">4.4</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?<BR>
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<A href="#4.4">4.4</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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ţ <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?<BR>
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<A href="#4.5">4.5</A>) <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>,
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<A href="#4.5">4.5</A>) <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>,
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?<BR>
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?<BR>
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<A href="#4.6">4.6</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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<A href="#4.6">4.6</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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@ -811,7 +812,7 @@
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<SMALL>DECLARE</SMALL>.</P>
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<SMALL>DECLARE</SMALL>.</P>
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<H4><A name="4.2">4.2</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <SMALL>SELECT</SMALL> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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<H4><A name="4.2">4.2</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <SMALL>SELECT</SMALL> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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<20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?</H4>
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<20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>? <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?</H4>
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<P><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <SMALL>FETCH</SMALL>
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<P><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <SMALL>FETCH</SMALL>
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<20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <SMALL>SELECT</SMALL> ... <SMALL>LIMIT</SMALL>....</P>
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<20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <SMALL>SELECT</SMALL> ... <SMALL>LIMIT</SMALL>....</P>
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@ -823,6 +824,14 @@
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD>
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD>
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><> <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>.</P>
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><> <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>.</P>
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<p>To <small>SELECT</small> a random row, use:
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</p><pre> SELECT col
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FROM tab
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ORDER BY random()
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LIMIT 1;
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</pre>
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</p>
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<H4><A name="4.3">4.3</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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<H4><A name="4.3">4.3</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <I>psql</I>?</H4>
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <I>psql</I>?</H4>
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@ -834,10 +843,11 @@
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<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>, <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD>
|
<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>, <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD>
|
||||||
<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>.</P>
|
<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>.</P>
|
||||||
|
|
||||||
<H4><A name="4.4">4.4</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?</H4>
|
<H4><A name="4.4">4.4</A>) <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD>
|
||||||
|
<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?</H4>
|
||||||
|
|
||||||
<P><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 7.3 <20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
|
<P><small>DROP COLUMN</small> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
|
||||||
<small>ALTER TABLE DROP COLUMN</small>. <20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>,
|
7.3 <20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <small>ALTER TABLE DROP COLUMN</small>. <20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>,
|
||||||
<20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD>:</P>
|
<20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD>:</P>
|
||||||
<PRE>
|
<PRE>
|
||||||
BEGIN;
|
BEGIN;
|
||||||
@ -850,6 +860,15 @@
|
|||||||
COMMIT;
|
COMMIT;
|
||||||
</PRE>
|
</PRE>
|
||||||
|
|
||||||
|
<P><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>, <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD>:</P>
|
||||||
|
<PRE>
|
||||||
|
BEGIN;
|
||||||
|
ALTER TABLE tab ADD COLUMN new_col <i>new_data_type</i>;
|
||||||
|
UPDATE tab SET new_col = CAST(old_col AS <i>new_data_type</i>);
|
||||||
|
ALTER TABLE DROP COLUMN old_col;
|
||||||
|
COMMIT;
|
||||||
|
</PRE>
|
||||||
|
|
||||||
<H4><A name="4.5">4.5</A>) <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>,
|
<H4><A name="4.5">4.5</A>) <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>,
|
||||||
<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?</H4>
|
<20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>?</H4>
|
||||||
|
|
||||||
|
Reference in New Issue
Block a user