Video: Yuav ua li cas koj xyuas seb ib yam dab tsi nyob rau hauv lub rooj SQL?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Rau kos yog rooj muaj nyob rau hauv ib tug database koj yuav tsum tau siv a Xaiv nqe lus ntawm tus cov ntaub ntawv schema TABSIS los yog koj siv tau tus metadata muaj nuj nqi OBJECT_ID(). Cov INFORMATION_SCHEMA. TABSIS rov ib kab rau txhua rooj hauv tus database tam sim no.
Ib yam li ib tug yuav nug, koj tuaj yeem qhia tau li cas yog tias lub rooj muaj nyob hauv cov ntaub ntawv?
Qhov yooj yim tshaj plaws kom pom tag nrho rooj hauv database yog nug cov all_tables saib : SELECT tus tswv, table_name FROM all_tables; Qhov no yuav ua yeeb yam tus tswv (tus neeg siv) thiab lub npe ntawm tus rooj . Koj tsis tas yuav muaj cai tshwj xeeb kom pom qhov no saib , tab sis nws tsuas qhia rooj uas nkag tau rau koj.
Qhov thib ob, siv li cas muaj nyob rau hauv SQL? Muaj yog ib tug predicate siv nyob rau hauv qhov chaw ntawm ib tug Transact- SQL ntawv SELECT nqe lus los ua SQL ntawv Server full-text search on full-text indexed columns muaj hom ntaub ntawv raws tus cwj pwm. Muaj tuaj yeem tshawb rau: Ib lo lus lossis kab lus. Lub prefix ntawm ib lo lus los yog kab lus.
Tsuas yog li ntawd, ua li cas koj tshawb xyuas cov ntaub ntawv hauv lub rooj SQL?
Right-click cov khoom rooj hauv SQL ntawv Server Object Explorer, thiab xaiv Saib Cov ntaub ntawv . Cov Cov ntaub ntawv Editor launches. Daim ntawv ceeb toom kab peb ntxiv rau cov rooj hauv cov txheej txheem yav dhau los. Right-click lub Fruits rooj hauv SQL ntawv Server Object Explorer, thiab xaiv Saib Cov ntaub ntawv.
Koj yuav kuaj xyuas li cas yog tias tus nqi hauv ib kab muaj nyob hauv lwm SQL?
Koj tuaj yeem siv MATCH() ua haujlwm rau kuaj yog tias tus tus nqi hauv kem Ib thiab muaj hauv kem B. MATCH() rov qab txoj hauj lwm ntawm a cell hauv a kab or kem . Cov syntax rau MATCH() yog = MATCH(lookup_value, lookup_array, [match_type]). Siv MATCH, koj tuaj yeem ua tau saib a tus nqi ob leeg horizontally thiab vertically.
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