object data type

Here is an example analysisTable A records the following:AID Anum1 a200501112 a200501123 a200501134 a200501145 a20050115Table B records the following:BID bname1 20060324012 20060324023 20060324034 20060324048 2006032408Create these two table SQL

To be honest, I've never used an index in a real project, just know that the index is a fairly important technical point, so I've seen a lot of articles about the differences, classifications, pros and cons of indexes, and how to use indexes. But

Tag: The operation condition operation will populate the same mem observation of the firstleft join returns records that include all the records in the left table and the equivalent of the junction fields in the right tableRight join returns records

Left join returns records that include all the records in the left table and the equivalent of the junction fields in the right tableRight join returns records that include all records in the right table and the junction fields in the left

Suppose there is a A, a, two table. Table A is recorded as follows: AID Anum1a200501112a200501123a200501134a200501145a20050115 table B is recorded as follows: BID bname1 2006032401 2 2006032402 3 2006032403 4 2006032404 8 2006

Here is an example analysisTable A records the following:AID Anum1 a200501112 a200501123 a200501134 a200501145 a20050115Table B records the following:BID bname1 20060324012 20060324023 20060324034 20060324048 2006032408Create these two table SQL

Left join returns records that include all the records in the left table and the equivalent of the junction fields in the right tableRight join returns records that include all records in the right table and the junction fields in the left

In large database applications, it is common to encounter partial data offline and multiple database consolidation issues. For example, there is now a province-wide application, each city has deployed a separate application server and database

(reproduced) http://www.cnblogs.com/pcjim/articles/799302.htmlLeft join returns records that include all the records in the left table and the equivalent of the junction fields in the right tableRight join returns records that include all records in

Pod extension is added in PHP5, which provides PHP built-in class PDO to access the database, different databases use the same method name, to solve the problem of non-uniform database connection.features of PDO:Performance. PDO has learned from the

Left join returns records that include all the records in the left table and the equivalent of the junction fields in the right tableRight join returns records that include all records in the right table and the junction fields in the left

The difference between the left join of SQL, right join, INNER joinLeft join returns records that include all the records in the left table and the equivalent of the junction fields in the right tableRight join returns records that include all

The SQL Server string is divided into different types, and you will be presented with a few common types of SQL Server strings that you can use to help you learn SQL Server strings.NCharThis data type can store 1~4000 fixed-length Unicode strings,

Left join returns records that include all the records in the left table and the equivalent of the junction fields in the right tableRight join returns records that include all records in the right table and the junction fields in the left

Left join returns records that include all the records in the left table and the equivalent of the junction fields in the right tableRight join returns records that include all records in the right table and the junction fields in the left

Left join returns records that include all the records in the left table and the equivalent of the junction fields in the right tableRight join returns records that include all records in the right table and the junction fields in the left

Regardless of the database, if you want to optimize the performance of the database, you must understand the storage structure inside the database. Otherwise, a lot of database optimization work can not be expanded. For the database administrator,

When you create a table, you can improve database performance by selecting the appropriate data type for the column.1. Select the appropriate data type to avoid data type conversions. For example, a date, someone using a string to hold the date,

Left join returns records that include all the records in the left table and the equivalent of the junction fields in the right tableRight join returns records that include all records in the right table and the junction fields in the left

written in front of the crap : The index problem has been a cliché, although it is often said, but as I have not used the index (very scary bar), I as a MS-BI implementation engineer incredibly useless index, speak naturally not emboldened. Prior to