![]() The semicolon ( ) is the statement terminator.The value is enclosed in single quotes (for example, WHERE last_name='Vader'). The WHERE clause selects only the rows in which the specified column contains the specified value.Use a comma and space between table names when specifying multiple tables. The FROM clause specifies one or more tables to be queried.To retrieve all columns, use the wild card ![]() The SELECT clause specifies one or more columns to be retrieved to specify multiple columns, use a comma and a space between column names.The syntax is: SELECT column1, column2 FROM table1, table2 WHERE column2='value' SELECT statementsĪn SQL SELECT statement retrieves records from a database table according to clauses (for example, FROM and The server then processes these statements and returns result sets to the client program. To do this, client programs send SQL statements to the server. Programs on client computers allow users to manipulate that data, using tables, columns, rows, and fields. In a distributed database system, a program often referred to as the database's "back end" runs constantly on a server, interpreting data files on the server as a standard relational database. It is widely used in both industry and academia, often for enormous, complex databases. A variety of established database products support SQL, including products from Oracle and Microsoft SQL Server. SQL is an ANSI and ISO standard, and is the de facto standard database query language. Structured Query Language (SQL) is a specialized language for updating, deleting, and requesting information fromĭatabases. The prefix of the tables are configurable in the User Source settings in the Gateway.SQL example statements for retrieving data from a table Extra properties are added for modules that want to associate data with a user, such as the Voice Notification Module, which adds a Security PIN setting. Each row is a new property and value pair, so users with multiple extra properties will have multiple rows in the table. This table stores a list of all extra properties for each user, with properties and values stored 1 for 1. Each row is a new contact information item, so users with multiple contact information items will have multiple rows in the table. This table stores a list of all contact information items for each user. Each row is a new schedule adjustment, so users with multiple schedule adjustments will have multiple rows in the table. This table stores a list of all upcoming schedule adjustments for each user. Each row is a user and a paired role, so users with multiple roles will have multiple rows in the table. This table stores a mapping of users to roles. This table stores all of the possible roles within the user source. This table stores each user contained within the user source, along with basic user information. This table stores annotations created by the user. If the tag is disabled, and then deleted, this value will also remain NULL. This value is NULL while the Tag is active. The tag group on the tag was changed, which results in a new row being created with the updated scid.Tags with Tag History enabled can be retired for any of the following reasons: ![]() Unix Timestamp (milliseconds since epoch) for when the Tag was retired. Unix Timestamp (milliseconds since epoch) for when the Tag's entry was created. 3: Values are stored using an Analog deadband style. Typically this column will only contain a 0 or 3:Ġ: Values are stored using a Discrete deadband style. The value here is based on the deadband style used to store the value. Which internal mode to use for returning data. 0: int, byte, short, boolean 1: float, double, long 2: string 3: date The tag group this Tag is storing values with. ![]() Path of the Tag in the Tag Provider, i.e., Folder1/tag1. This table stores annotations for the Tag history system, such as those created by the Power Chart This table stores information about the drivers of the historical data. This table stores start and end times for each sqlt_data table. This table stores start and end times for tag groups. This table stores the non-data details of each Tag. This table stores raw Tag data, and is only used when the provider is configured to use a single partition ( The provider's "Enable Partitioning" setting is unchecked). For example, a table named "sqlt_data_1_2018_01" would storing data from the driver with an id of 1, for the year 2018, for the month of January) ![]() There will be multiple tables that fit this format depending on the name of the Gateway and the date. ![]()
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