大约有 47,000 项符合查询结果(耗时:0.0586秒) [XML]

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I want to copy table contained from one database and insert onto another database table

...as below. CREATE TABLE db2.table LIKE db1.table; INSERT INTO db2.table SELECT * FROM db1.table; share | improve this answer | follow | ...
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When should I use semicolons in SQL Server?

...llowing two queries (copied from this post): BEGIN TRY BEGIN TRAN SELECT 1/0 AS CauseAnException COMMIT END TRY BEGIN CATCH SELECT ERROR_MESSAGE() THROW END CATCH BEGIN TRY BEGIN TRAN SELECT 1/0 AS CauseAnException; COMMIT END TRY BEGIN CATCH SELECT ERROR_MES...
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IndexOf function in T-SQL

... CHARINDEX is what you are looking for select CHARINDEX('@', 'someone@somewhere.com') ----------- 8 (1 row(s) affected) -or- select CHARINDEX('c', 'abcde') ----------- 3 (1 row(s) affected) ...
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Delete all records in a table of MYSQL in phpMyAdmin

...ampserver 2.2. When I want to delete all records of a table in phpMyAdmin (select all) it deletes only one record not all records. Why it does not delete all records? ...
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How to call a stored procedure from Java and JPA

...s ( postId IN NUMBER, commentCount OUT NUMBER ) AS BEGIN SELECT COUNT(*) INTO commentCount FROM post_comment WHERE post_id = postId; END; You can call it from JPA as follows: StoredProcedureQuery query = entityManager .createStoredProcedureQuery("count_comments"...
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How to export DataTable to Excel

...tring[] columnNames = dataTable.Columns .Cast<DataColumn>() .Select(column => column.ColumnName) .ToArray(); var header = string.Join(",", columnNames.Select(name => $"\"{name}\"")); lines.Add(header); var valueLines = dataTable.AsEnumerable() .Select(row => string.J...
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How to apply two CSS classes to a single element

...To target elements that contain all of the specified classes, use this CSS selector (no space) (ref): .c1.c2 { } share | improve this answer | follow | ...
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Pandas conditional creation of a series/dataframe column

... If you only have two choices to select from: df['color'] = np.where(df['Set']=='Z', 'green', 'red') For example, import pandas as pd import numpy as np df = pd.DataFrame({'Type':list('ABBC'), 'Set':list('ZZXY')}) df['color'] = np.where(df['Set']=='Z', ...
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MySQL和MongoDB设计实例进行对比 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术

...并且外观设计是直板的手机,需按照如下方式查询: SELECT * FROM `mobile_params` WHERE name = '待机时间' AND value > 100; SELECT * FROM `mobile_params` WHERE name = '外观设计' AND value = '直板'; 注:参数表为了方便,把数值和字符串统一保存成字...
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Should I use the datetime or timestamp data type in MySQL?

...o with the native format. You can do calculations within MySQL that way ("SELECT DATE_ADD(my_datetime, INTERVAL 1 DAY)") and it is simple to change the format of the value to a UNIX timestamp ("SELECT UNIX_TIMESTAMP(my_datetime)") when you query the record if you want to operate on it with PHP. ...