Data Source Sharing Interaction (Magic xpa 4.x)
The following table describes the sharing interaction between two tasks opening the same data source. A plus sign (+) indicates that modes are compatible while a minus sign (–) indicates that modes are incompatible.
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Process A
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Access Mode
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Read
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Write
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Mode
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Share Mode
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Read
|
Write
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None
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Read
|
Write
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None
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Mode
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|
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Process B
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Read
|
Read
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+
|
+
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–
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+
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+
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–
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|
|
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Write
|
|
+
|
+
|
–
|
+
|
+
|
–
|
|
|
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None
|
|
–
|
–
|
–
|
–
|
–
|
–
|
|
|
Write
|
Read
|
|
–
|
+
|
–
|
–
|
–
|
–
|
|
|
|
Write
|
|
–
|
+
|
–
|
–
|
+
|
–
|
|
|
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None
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|
–
|
–
|
–
|
–
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–
|
–
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Valid Access Modes
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For example, if Process A opens the table in R/R mode (that is, Access=R and Share=R), Process B can open the same table with modes R/R and R/W.
If process A opens the table in R/W mode, process B can open the table in R/R, R/W, W/R, or W/W modes.
