Cov txheej txheem:
Video: Kuv yuav suav cov ntxhuav hauv MySQL li cas?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Mus xyuas lub suav ntawm rooj . mysql > SELECT suav (*) AS TOTALNUMBEROFTABLES -> NTAWM INFORMATION_SCHEMA. TABSIS -> WHERE TABLE_SCHEMA = 'ua lag luam'; Cov zis hauv qab no muab cov suav ntawm tag nrho cov rooj.
Kuj kom paub yog, kuv tuaj yeem pom txhua lub rooj hauv MySQL li cas?
Hauv MySQL muaj ob txoj hauv kev nrhiav npe of tag nrho cov rooj , los ntawm kev siv "show" lo lus tseem ceeb lossis los ntawm kev nug INFORMATION_SCHEMA. Nyob rau hauv rooj plaub ntawm SQL Server lossis MSSQL, Koj tuaj yeem siv sys. rooj los yog INFORMATION_SCHEMA rau tau tag nrho cov npe rooj rau a database.
Kuv tuaj yeem pom cov ntxhuav hauv database li cas? Txhawm rau sau / qhia cov ntxhuav hauv MySQL database:
- Nkag mus rau hauv koj lub database siv mysql hais kom ua kab tus neeg siv khoom.
- Tshaj tawm cov lus txib siv los txuas rau koj cov ntaub ntawv xav tau (xws li, siv mydatabase)
- Siv MySQL qhia cov lus hais kom ua, zoo li no:
Ua li no, kuv yuav suav cov lej ntawm kab hauv ib lub rooj hauv MySQL li cas?
mysql > SELECT COUNT (*) AS NUMBEROFCOLUMNS NTAWM INFORMATION_SCHEMA. COLUMNS -> WHERE table_schema = 'kev lag luam' THIAB table_name = 'NumberOfColumns'; Cov zis tso saib cov tus naj npawb ntawm kab.
Kuv yuav saib lub rooj hauv SQL li cas?
Yuav Ua Li Cas Saib Ib Lub Rooj hauv SQL Server Database
- Ua ntej, koj yuav tsum qhib Enterprise Manager thiab nthuav cov npe SQL Server.
- Nthuav Databases kom pom cov npe databases ntawm server.
- Nrhiav thiab nthuav cov ntaub ntawv tshwj xeeb uas muaj lub rooj uas koj xav pom.
- Nyem rau ntawm Tables, uas yuav qhia tag nrho cov ntxhuav hauv cov ntaub ntawv hauv lub pane mus rau sab xis.
Pom zoo:
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Cov cuab yeej wc yog 'lo lus txee' hauv UNIX thiab UNIX zoo li kev khiav haujlwm, koj tuaj yeem siv nws los suav cov kab hauv cov ntaub ntawv, los ntawm kev ntxiv cov kev xaiv -l, yog li wc -l foo yuav suav cov kab hauv foo
Dab tsi yog cov lus nug siv los tso saib tag nrho cov npe ntawm cov ntxhuav hauv SQL Server?
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Kuv yuav tso tag nrho cov ntxhuav hauv MySQL schema li cas?
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Kuv yuav sau tag nrho cov ntxhuav hauv SQL database li cas?
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